Indicate by check mark whether the registrant (1) has filed all reports required to be filed by Section 13 or 15(d) of the Securities Exchange Act of 1934 during the preceding 12 months (or for such shorter period that the registrant was required to file such reports), and (2) has been subject to such filing requirements for the past 90 days. Yes ☒ No ☐

Indicate by check mark whether the registrant has submitted electronically every Interactive Data File required to be submitted pursuant to Rule 405 of Regulation S-T (§232.405 of this chapter) during the preceding 12 months (or for such shorter period that the registrant was required to submit such files). Yes ☒ No ☐

Indicate by check mark whether the registrant is a large accelerated filer, an accelerated filer, a non-accelerated filer, a smaller reporting company, or an emerging growth company. See the definitions of “large accelerated filer,” “accelerated filer,” “smaller reporting company,” and “emerging growth company” in rule 12b-2 of the Exchange Act.

If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 13(a) of the Exchange Act. ☐

Indicate by check mark whether the registrant is a shell company (as defined in Rule 12b-2 of the Exchange Act). Yes☐ No ☒

	March 31, 2021			December 31, 2020			September 30, 2021			December 31, 2020
Assets
Current assets:
Cash and cash equivalents	$	56,818		$	45,219		$	45,505		$	45,219
Restricted cash		6,848			9,200			6,884			9,200
Accounts receivable - trade, net of allowance for doubtful accounts of $17.9 million as of March 31, 2021 and $4.0 million as of December 31, 2020		82,028			97,253
Accounts receivable - trade, net of allowance for doubtful accounts of $18,170 as of September 30, 2021 and $4,000 as of December 31, 2020								84,730			97,253
Other receivables		10,159			9,165			12,477			9,165
Inventories		41,116			39,572			58,270			39,572
Contract assets		6,233			6,182			3,466			6,182
Prepaid expenses and other current assets		7,603			5,332			8,906			5,332
Total current assets		210,805			211,923			220,238			211,923
Property, plant and equipment, net		7,880			7,146			9,256			7,146
Right-of-use assets from operating leases		14,535			18,483			12,932			18,483
Goodwill		5,675			3,977			6,145			3,977
Intangible assets, net		6,759			3,377			5,409			3,377
Deferred tax assets		1,633			1,405			1,156			1,405
Other assets		5,589			5,919			8,826			5,919
Total assets	$	252,876		$	252,230		$	263,962		$	252,230
Liabilities and Stockholders’ Equity
Current liabilities:
Accounts payable - trade	$	50,955		$	49,250		$	67,953		$	49,250
Short-term debt - bank, trade facilities and secured borrowings		1,764			13,787			-			13,787
Contract liabilities		3,997			4,400			4,585			4,400
Operating lease liabilities		4,435			4,494			4,118			4,494
Accrued and other liabilities		18,941			16,707			21,802			16,707
Total current liabilities		80,092			88,638			98,458			88,638
Long-term debt
Related party		—			29,754
Contract liabilities		2,495			2,471
Long-term debt - related party								-			29,754
Contract liabilities - non-current								2,951			2,471
Operating lease liabilities - non-current		16,154			15,959			12,694			15,959
Pension liabilities		18,936			20,052			18,685			20,052
Other long-term liabilities		3,697			1,777			3,426			1,777
Total liabilities		121,374			158,651			136,214			158,651
Commitments and contingencies (Note 14)
Stockholders’ equity:
Common stock, authorized 36,000 shares, 26,883 and 21,958 shares outstanding as of March 31, 2021 and December 31, 2020, respectively, at $0.001 par value		27			22
Common stock, 36,000 shares authorized, 27,207 and 21,958 shares issued and outstanding as of September 30, 2021 and December 31, 2020, respectively, at $0.001 par value								27			22
Additional paid-in capital		211,438			147,997			218,596			147,997
Accumulated other comprehensive loss		(4,422	)		(2,124	)		(6,159	)		(2,124	)
Accumulated deficit		(75,541	)		(52,316	)		(84,716	)		(52,316	)
Total stockholders’ equity		131,502			93,579			127,748			93,579
Total liabilities and stockholders’ equity	$	252,876		$	252,230		$	263,962		$	252,230

See accompanying notes to unaudited condensed consolidated financial statements.

Three Months Ended

March 31,

2021

2020

Net revenue

$
81,031

$
47,480

Cost of revenue

52,936

31,485

Gross profit

28,095

15,995

Operating expenses:

Research and product development

11,119

9,710

Selling, marketing, general and administrative

31,824

13,507

Restructuring and other charges

6,252

—

Impairment of long-lived assets

1,735

—

Amortization of intangible assets

262

372

Total operating expenses

51,192

23,589

Operating income (loss)

(23,097
)

(7,594
)
Interest income

42

70

Interest expense

(249
)

(643
)
Loss on extinguishment of debt

—

(1,369
)
Other income (expense), net

972

760

Income (loss) before income taxes

(22,332
)

(8,776
)
Income tax provision (benefit)

893

(5
)
Net income (loss)

(23,225
)

(8,771
)

Foreign currency translation adjustments

(2,270
)

(3,435
)
Actuarial gain (loss)

(28
)

1,456

Comprehensive income (loss)

$
(25,523
)

$
(10,750
)
Net income (loss) per share

Basic

$
(0.92
)

$
(0.41
)
Diluted

$
(0.92
)

$
(0.41
)
Weighted average shares outstanding used to
compute basic net income (loss) per share

25,252

21,474

Weighted average shares outstanding used to
compute diluted net income (loss) per share

25,252

21,474

	Three Months Ended				Nine Months Ended
	September 30,				September 30,
	2021		2020		2021		2020
Net revenue	$	88,412	$	93,947	$	252,143	$	211,959

Cost of revenue	56,213			65,755			164,771			144,004
Gross profit	32,199			28,192			87,372			67,955
Operating expenses:
Research and product development	11,707			9,033			34,788			27,238
Selling, marketing, general and administrative	19,539			16,795			69,619			43,472
Restructuring and other charges	6,754			-			12,098			-
Impairment of long-lived assets	-			-			1,735			-
Amortization of intangible assets	312			387			888			1,130
Total operating expenses	38,312			26,215			119,128			71,840
Operating income (loss)	(6,113	)		1,977			(31,756	)		(3,885	)
Interest income	20			14			81			98
Interest expense	(49	)		(446	)		(326	)		(1,503	)
Loss on extinguishment of debt	-			—			-			(1,369	)
Other income (expense), net	922			(41	)		1,633			69
Income (loss) before income taxes	(5,220	)		1,504			(30,368	)		(6,590	)
Income tax provision (benefit)	676			1,619			2,032			2,452
Net income (loss)	(5,896	)		(115	)		(32,400	)		(9,042	)
							-
Foreign currency translation adjustments	(2,036	)		1,112			(4,090	)		(1,519	)
Actuarial gain (loss)	—			—			55			285
Comprehensive income (loss)	(7,932	)	$	997		$	(36,435	)	$	(10,276	)
Net income (loss) per share
Basic	(0.22	)	$	(0.01	)	$	(1.22	)	$	(0.42	)
Diluted	(0.22	)	$	(0.01	)	$	(1.22	)	$	(0.42	)
Weighted average shares outstanding used to compute basic net income (loss) per share	27,201			21,592			26,484			21,532
Weighted average shares outstanding used to compute diluted net income (loss) per share	27,201			21,592			26,484			21,532

See accompanying notes to unaudited condensed consolidated financial statements.

	Common stock				Additional paid-in		Accumulated other comprehensive			Accumulated			Total stockholders'			Common stock				Additional paid-in		Accumulated other comprehensive			Accumulated			Total stockholders'
	Shares		Amount		capital		loss			deficit			equity			Shares		Amount		capital		loss			deficit			equity
For the Three-Month Period Ended March 31, 2021:
For the Nine-Month Period Ended September 30, 2021:
Balance as of December 31, 2020		21,958	$	22	$	147,997	$	(2,124	)	$	(52,316	)	$	93,579			21,958	$	22	$	147,997	$	(2,124	)	$	(52,316	)	$	93,579
Issuance of common stock in public offering, net of issuance costs		4,600		5		59,520		—			—			59,525			4,600		5		59,520		—			—			59,525
Exercise of stock awards and employee stock plan purchases		325		—		2,569		—			—			2,569			325		—		2,569		—			—			2,569
Stock-based compensation		—		—		1,352		—			—			1,352			—		—		1,352		—			—			1,352
Net income (loss)		—		—		—		—			(23,225	)		(23,225	)		—		—		—		—			(23,225	)		(23,225	)
Other comprehensive loss		—		—		—		(2,298	)		—			(2,298	)		—		—		—		(2,298	)		—			(2,298	)
Balance as of March 31, 2021		26,883	$	27	$	211,438	$	(4,422	)	$	(75,541	)	$	131,502			26,883	$	27	$	211,438	$	(4,422	)	$	(75,541	)	$	131,502
Exercise of stock awards and employee stock plan purchases																	309		—		1,967		—			—			1,967
Stock-based compensation																	—		—		1,994		—			—			1,994
Net income (loss)																	—		—		—		—			(3,279	)		(3,279	)
Other comprehensive loss																	—		—		—		299			—			299
Balance as of June 30, 2021																	27,192	$	27	$	215,399	$	(4,123	)	$	(78,820	)	$	132,483
Exercise of stock awards and employee stock plan purchases																	15		—		93		—			—			93
Stock-based compensation																	—		—		3,104		—			—			3,104
Net income (loss)																	—		—		—		—			(5,896	)		(5,896	)
Other comprehensive loss																	—		—		—		(2,036	)		—			(2,036	)
Balance as of September 30, 2021																	27,207	$	27	$	218,596	$	(6,159	)	$	(84,716	)	$	127,748

For the Three-Month Period Ended March 31, 2020:


For the Nine-Month Period Ended September 30, 2020:
Balance as of December 31, 2019		21,419	$	21	$	139,700	$	(3,939	)	$	(29,234	)	$	106,548			21,419	$	21	$	139,700	$	(3,939	)	$	(29,234	)	$	106,548
Exercise of stock awards and employee stock plan purchases		94		—		709		—			—			709			94		—		709		—			—			709
Stock-based compensation		—		—		782		—			—			782			—		—		782		—			—			782
Net income (loss)		—		—		—		—			(8,771	)		(8,771	)		—		—		—		—			(8,771	)		(8,771	)
Other comprehensive loss		—		—		—		(1,979	)		—			(1,979	)		—		—		—		(1,979	)		—			(1,979	)
Balance as of March 31, 2020		21,513	$	21	$	141,191	$	(5,918	)	$	(38,005	)	$	97,289			21,513	$	21	$	141,191	$	(5,918	)	$	(38,005	)	$	97,289

Exercise of stock awards and employee stock plan purchases																	46		—		284		—			—			284
Stock-based compensation																	—		—		868		—			—			868
Net income (loss)																	—		—		—		—			(156	)		(156	)
Other comprehensive loss																	—		—		—		(367	)		—			(367	)
Balance as of June 30, 2020																	21,559	$	21	$	142,343	$	(6,285	)	$	(38,161	)	$	97,918
Exercise of stock awards and employee stock plan purchases																	63		1		269		—			—			270
Stock-based compensation																	—		—		1,660		—			—			1,660
Net income (loss)																	—		—		—		—			(115	)		(115	)
Other comprehensive loss																	—		—		—		1,112			—			1,112
Balance as of September 30, 2020																	21,622	$	22	$	144,272	$	(5,173	)	$	(38,276	)	$	100,845

See accompanying notes to unaudited condensed consolidated financial statements.

	Three Months Ended						Nine months ended
	March 31,						September 30,
	2021			2020			2021			2020
Cash flows from operating activities:
Net income (loss)	$	(23,225	)	$	(8,771	)	$	(32,400	)	$	(9,042	)
Adjustments to reconcile net income (loss) to net cash provided by (used in) operating activities:
Depreciation and amortization		1,265			1,256			3,555			3,935
Impairment of long-lived assets		4,443			—
Impairment of long-lived assets and non-cash restructuring								4,475			—
Gain on Lease termination								(908	)		—
Loss on extinguishment of debt		—			1,343			—			1,343
Amortization of deferred financing costs		12			141			12			147
Stock-based compensation		1,352			782			6,450			3,310
Provision for inventory write-down		666			1,421			2,928			4,079
Allowance for doubtful accounts		14,805			24
Bad debt expense								14,579			446
Provision for sales returns		239			(231	)		873			556
Provision for warranty		269			—			636			341
Unrealized gain on foreign currency transactions		(883	)		(1,983	)		47			(405	)
Deferred taxes		(134	)		(820	)		139			(224	)
Changes in operating assets and liabilities:
Accounts receivable		(1,423	)		9,109			(3,945	)		(16,582	)
Other receivable								(7,648	)		(1,153	)
Inventories		(3,239	)		14,129			(24,256	)		(11,984	)
Contract assets		(267	)		(7,048	)		2,557			11,609
Prepaid expenses and other assets		(3,864	)		(3,285	)		(7,063	)		(805	)
Accounts payable		3,539			(1,261	)		21,991			2,217
Contract liabilities		32			(275	)		631			(131	)
Accrued and other liabilities		(523	)		(3,937	)		2,282			1,348
Net cash provided by (used in) operating activities		(6,936	)		594			(15,065	)		(10,995	)
Cash flows from investing activities:
Purchases of property, plant and equipment		(1,266	)		(560	)		(4,158	)		(1,947	)
Acquisition of business, net of cash acquired		(4,258	)		—			(4,459	)		—
Net cash used in investing activities		(5,524	)		(560	)		(8,617	)		(1,947	)
Cash flows from financing activities:
Proceeds from issuance of common stock in public offerings, net of issuance costs		59,525			—			59,525			—
Proceeds from short-term borrowings and line of credit		—			1,307			—			13,774
Repayments of short-term borrowings and line of credit		(11,494	)		(4,167	)		(13,278	)		(12,077	)
Repayments of long-term borrowings		—			(13,125	)		—			(13,125	)
Proceeds from related party term loan		—			18,361			—			18,361
Repayments of related party term loan		(29,298	)		—			(29,298	)		—
Proceeds from factored accounts receivable								—			11,645
Deferred financing costs								—			(20	)
Proceeds from exercise of stock awards and employee stock plan purchases		2,569			709			4,629			1,262
Net cash provided by financing activities		21,302			3,085			21,578			19,820
Effect of exchange rate changes on cash, cash equivalents and restricted cash		404			(873	)		71			47
Net increase in cash, cash equivalents and restricted cash		9,246			2,246			(2,033	)		6,925
Cash, cash equivalents and restricted cash at beginning of period		54,587			33,635			54,587			33,635
Cash, cash equivalents and restricted cash at end of period	$	63,833		$	35,881		$	52,554		$	40,560

Reconciliation of cash, cash equivalents and restricted cash to statement of financial position
Cash and cash equivalents	$	56,818		$	26,437		$	45,505		$	31,307
Restricted cash		6,848			9,281			6,884			9,087
Long-term restricted cash		167			163			165			166
	$	63,833		$	35,881		$	52,554		$	40,560

Supplemental disclosure of cash flow information:
Cash paid during the period for:
Interest - bank and trade facilities	$	83		$	424		$	83		$	616
Interest - related party	$	94		$	152		$	108		$	888
Income taxes	$	1,206		$	1,504		$	3,029		$	2,587

See accompanying notes to unaudited condensed consolidated financial statements.

DZS Inc. (referred to, collectively with its subsidiaries, as “DZS” or the “Company”) is a global provider of ~~ultra-broadband network access~~optical and packet-based mobile transport, broadband connectivity, and software defined networking solutions ~~and communications platforms~~ deployed by advanced Tier 1, national and regional service providers and enterprise customers. The Company provides a wide array of reliable, cost-effective networking technologies, including broadband access, Ethernet switching, mobile backhaul, Passive Optical LAN and software-defined networks, to a diverse customer base.

DZS was incorporated under the laws of the state of Delaware in June 1999. The Company is headquartered in Plano, Texas with flexible in-house production facilities in Seminole, Florida, ~~and Hanover, Germany,~~ and contract manufacturers located in China, India, Korea and Vietnam. The Company also maintains offices to provide sales and customer support at global locations.

The accompanying unaudited condensed consolidated financial statements have been prepared in accordance with U.S. GAAP for interim financial information and with the instructions to Form 10-Q and Article 8 of Regulation S-X. Accordingly, they do not include all of the information and footnotes required by U.S. GAAP for complete financial statements. These financial statements include the accounts of the Company and its wholly owned subsidiaries. These unaudited condensed consolidated financial statements should be read in conjunction with the consolidated financial statements of the Company and notes thereto included in the Company’s Annual Report on Form 10-K for the year ended December 31, 2020 filed with the Securities and Exchange Commission (“SEC”) on March 11, 2021. For a complete description of what the Company believes to be the critical accounting policies and estimates used in the preparation of its unaudited condensed consolidated financial statements, refer to the Company’s Annual Report on Form 10-K for the year ended December 31, 2020.

All intercompany transactions and balances have been eliminated in consolidation. Certain prior-year amounts have been reclassified to conform to the current-quarter presentation. The unaudited condensed consolidated financial statements reflect all adjustments (consisting only of normal recurring adjustments) that, in the opinion of management, are necessary for a fair presentation of the results for the interim periods presented. The results of operations for the current interim period are not necessarily indicative of results to be expected for the current year or any other period.

The accompanying unaudited condensed consolidated financial statements have been prepared in conformity with U.S. GAAP, assuming the Company will continue as a going concern.

In December 2019, a strain of coronavirus, now known asto cause COVID-19, was reported to have surfaced in Wuhan, China. Since that time, the widespread and sustained transmission of the virus has reached global pandemic status. In response to the pandemic, many national and international health agencies have recommended, and many countries and state, provincial and local governments have implemented, various measures, including travel bans and restrictions, limitations on public and private gatherings, business closures or operating restrictions, social distancing, and shelter-in-place orders. The health effects of the pandemic and the above measures taken in response thereto have had an effect on the global economy in general and have materially impacted and will likely continue to impact the Company’s financial condition, results of operations and cash flows. Given the ongoing and dynamic nature of the virus and the worldwide response related thereto, it is difficult to predict the full impact of the COVID-19 pandemic on our business. Due to the uncertainty around the future economic impact of the pandemic, the fair value measurements used in the Company’s impairment assessments could be negatively impacted and could result in future impairments of goodwill, intangibles and other long-lived assets. During the ~~three~~nine months ended ~~March 31,~~September 30, 2021, the Company’s revenues increased by ~~70.7%~~19.0%, compared to the ~~three~~nine months ended ~~March 31,~~September 30, 2020, however, the impact of a continued COVID-19 pandemic or sustained measures taken to limit or contain the outbreak could have a material and adverse effect on our business, financial condition, results of operations, and cash flows.

The preparation of the unaudited condensed consolidated financial statements in conformity with U.S. GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities at the date of the unaudited condensed consolidated financial statements and the reported amounts of revenue and expenses during the reporting period. Actual results could differ materially from those estimates.

	Three Months Ended March 31,				Three Months Ended September 30,				Nine Months Ended September 30,
	2021		2020		2021		2020		2021		2020
Revenue by source:
Products	$	76,252	$	42,719	$	82,911	$	88,910	$	237,083	$	197,832
Services		4,779		4,761
Services and other						5,501		5,037		15,060		14,127
Total	$	81,031	$	47,480	$	88,412	$	93,947	$	252,143	$	211,959

The following table present revenues by geographical concentration (in thousands):

	Three Months Ended March 31,				Three Months Ended September 30,				Nine Months Ended September 30,
	2021		2020		2021		2020		2021		2020
Revenue by geography:
Americas	$	20,169	$	11,702	$	27,302	$	16,904	$	73,984	$	43,741
Europe, Middle East, Africa		17,918		11,339		20,380		19,964		54,999		47,740
Asia		42,944		24,439		40,730		57,079		123,160		120,478
Total	$	81,031	$	47,480	$	88,412	$	93,947	$	252,143	$	211,959

Financial instruments that potentially subject the Company to concentrations of credit risk consist primarily of cash, cash equivalents and restricted cash, accounts receivables, and contract assets. Cash, cash equivalents and restricted cash consist of financial deposits and money market accounts that are principally held with various domestic and international financial institutions with high credit standing.

The Company’s customers include competitive and incumbent local exchange carriers, competitive access providers, internet service providers, wireless carriers and resellers serving these markets. The Company performs ongoing credit evaluations of its customers and generally does not require collateral. Allowances are maintained for potential doubtful ~~accounts.~~ accounts based upon the expected collectability of accounts receivable. The Company bases its allowance on periodic assessments of its customers’ liquidity and financial condition through analysis of information obtained from credit rating agencies, financial statement review and historical and current collection trends, as well as on specific balances where collectability may be uncertain.

For the three months ended ~~March 31,~~September 30, 2021, 2 customers accounted for 15% and 11% of net revenue, respectively. For the nine months ended September 30, 2021, 2 customers accounted for 18% and ~~10%~~12% of net revenue, respectively. For the three months ended ~~March 31,~~September 30, 2020, 2 customers accounted for ~~14%~~23% and ~~10%~~12% of net revenue, respectively. For the nine months ended September 30, 2020, 1 customer accounted for 16% of net revenue.

As of ~~March 31,~~September 30, 2021, ~~1 customer~~2 customers represented ~~19%~~18% and 15% of net accounts ~~receivable.~~receivable, respectively. As of December 31, 2020, 2 customers represented 17% and 16% of net accounts receivable, respectively.

As of ~~March 31,~~September 30, 2021, and December 31, 2020, net accounts receivables from customers in countries other than the United States represented ~~84%~~80% and 89%, respectively.

In 2017, the Company entered into an agreement with a customer in India to supply product for a state sponsored broadband project. The Company billed the customer, which is a state government sponsored entity, approximately $59.0 million and collected payments of approximately $41.7 million, leaving a balance of approximately $17.3 million as of December 31, 2020. The Company substantially completed its obligations under the agreement in 2018, and all amounts due were billed under the terms of the agreement by December 31, 2020. The remaining $17.3 million is substantially beyond the customers contractual payment terms, and the Company has been actively working with the customer and third parties in India to arrange payment of the entire remaining balance of $17.3 million. The Company recorded an allowance for doubtful accounts of $3.1 million on December 31, 2020, for a partial payment promised but not received. In late March 2021, the customer’s state government parent experienced difficulty passing a budget further impacting the ability of the customer to make agreed-upon partial payments to us. In light of this ~~recent~~ development, ~~in the first quarter of 2021,~~ the Company recognized an additional allowance of $14.2 million during the three months ended March 31, 2021, to bring the total allowance for the customer to $17.3 million, which is the total balance as of ~~March 31,~~September 30, 2021. The Company will continue to pursue collection of the entire outstanding balance and any amounts collected will be recognized in the period which they are received. In the event the Company’s efforts to collect from this customer prove unsuccessful, DZS may seek payment through other means, including through legal action.

The Company allocates the fair value of purchase consideration to the tangible and identifiable intangible assets acquired and liabilities assumed based on their estimated fair values. The excess of the fair value of purchase consideration over the fair values of these identifiable assets and liabilities is recorded as goodwill. When determining the fair values of assets acquired and liabilities assumed, management makes significant estimates and assumptions, especially with respect to intangible assets and certain tangible assets such as inventory.

Critical estimates in valuing certain tangible and intangible assets include but are not limited to future expected cash flows from the underlying assets and discount rates. Management’s estimates of fair value are based upon assumptions believed to be reasonable, but which are inherently uncertain and unpredictable and, as a result, actual results may differ from estimates.

Assets acquired and liabilities assumed are generally measured at their acquisition-date fair values. If the initial accounting for a business combination is incomplete by the end of the reporting period in which the combination occurs, the Company reports provisional amounts for the items for which the accounting is incomplete. Those provisional amounts are adjusted during the measurement period (which cannot exceed one year from the acquisition date), or additional assets or liabilities are recognized, to reflect new information obtained about facts and circumstances that existed as of the acquisition date that, if known, would have affected the amounts recognized as of that date.

When the consideration transferred by the Company in a business combination includes a contingent consideration arrangement, the contingent consideration is measured at its acquisition-date fair value and included as part of the total consideration transferred in a business combination. Changes in fair value of the contingent consideration that qualify as measurement period adjustments are made retrospectively, with corresponding adjustments against goodwill. Changes in the fair value of the contingent consideration that do not qualify as measurement period adjustments are made in the current period, with corresponding adjustments recognized in earnings.

Restructuring and other charges primarily consists of severance and other termination benefits and non-cash impairment charges related to right-of-use assets from operating leases related to the restructuring activities in Hanover, ~~Germany.~~Germany and Ottawa, Canada. The Company recognizes contractual termination benefits when it is probable that employees will be entitled to benefits and the amount can be reasonably estimated. The Company ~~will recognize~~recognizes one-time employee termination benefits when (i) management commits to a plan of termination, (ii) the plan identifies the number of employees to be terminated, their job classifications or functions and their locations, and the expected completion date, (iii) the plan establishes the terms of the benefit arrangement in sufficient detail to enable employees to determine the type and amount of benefits they will receive, and (iv) actions required to complete the plan indicate that it is unlikely that significant changes to the plan will be made or that the plan will be withdrawn. These charges are included in restructuring and other charges in the unaudited condensed consolidated statement of comprehensive income (loss). Refer to Note 9 Restructuring and Other Charges for further information.

In June 2016, the Financial Accounting Standards Board (“FASB”) issued Accounting Standards Update (“ASU”) 2016-13, Financial Instruments - Credit Losses (Topic 326): Measurement of Credit Losses on Financial Instruments, which requires the Company to measure and recognize expected credit losses for financial assets held and not accounted for at fair value through net income. In November 2018, April 2019 and May 2019, the FASB issued ASU No. 2018-19, Codification Improvements to Topic 326, Financial Instruments - Credit Losses, ASU No. 2019-04, Codification Improvements to Topic 326, Financial Instruments - Credit Losses, and ASU No. 2019-05, Financial Instruments - Credit Losses (Topic 326): Targeted Transition Relief, which provided additional implementation guidance on the previously issued ASU. The Company expects to adopt the updated guidance on January 1, 2022, ~~and requires a~~utilizing the modified retrospective ~~adoption method. Early adoption~~transition method through a cumulative-effect adjustment to retained earnings. The ASU is ~~permitted. The Company is currently assessing the potential~~not expected to have a material impact ~~of adopting this new guidance~~ on ~~its~~our consolidated financial statements.

In March 2020, the FASB issued ASU No. 2020-04 (Topic 848), Reference Rate Reform - Facilitation of the Effects of Reference Rate Reform on Financial Reporting, which provides temporary optional expedients and exceptions to the existing guidance on contract modifications and hedge accounting to ease the financial reporting burdens related to the expected market transition from the London Interbank Offered Rate (LIBOR) and other interbank offered rates to alternative reference rates, such as the Secured Overnight Financing Rate. The standard was effective upon issuance and may generally be applied through December 31, 2022, to any new or amended contracts, hedging relationships, and other transactions that reference LIBOR. The ~~Company is currently evaluating the impact of the transition and disclosure requirements of the standard on its consolidated financial statements.~~

~~In December 2019, the FASB issued ASU 2019-12:~~ ~~Simplifying the Accounting for Income Taxes~~ ~~(Topic 740), which removes certain exceptions to the general principles in Topic 740 and improves consistent application of and simplifies GAAP for other~~

~~areas of Topic 740 by clarifying and amending existing guidance. This~~ ASU is effective for fiscal years beginning after December 15, 2020, and interim periods within those fiscal years, with early adoption permitted. The Company adopted this new accounting standard effective January 1, 2021 which did not expected to have a material impact on ~~the Company's~~our consolidated financial ~~statements or disclosures.~~statements.

On February 5, 2021, the Company acquired Optelian Access Networks Corporation (“Optelian”), a corporation incorporated under the laws of Canada and registered extra-provincially in the Province of Ontario, pursuant to an acquisition agreement whereby the Company purchased all the outstanding shares of Optelian (the “Optelian Acquisition”). Following the closing of the Optelian Acquisition, Optelian became the Company’s wholly owned subsidiary.

Optelian iswas a leading optical networking solution provider. This acquisition introduced the “O-Series” to the DZS portfolio of carrier grade optical networking products with 100 gigabits per second (Gig) and above capability, expanding DZS product portfolios by providing environmentally hardened, high capacity, and flexible solutions at the network edge.

The purchase price of $7.5 million included cash paid to the shareholders and option holders of Optelian, cash paid to retire Optelian's outstanding debt on the date of acquisition, and contingent payments to shareholders (in thousands):

The ~~future payments are contingent on certain working capital adjustments~~payment to shareholders and option holders includes a $0.3 million holdback and $1.9 million contingent consideration based on a certain percentage of future revenue of certain Optelian products through the end of 2023.

The acquisition was recorded as a business combination with valuations of the assets acquired and liabilities assumed at their acquisition date fair value using level three inputs, defined as unobservable inputs that are supported by little or no market activity and that are significant to the fair value of the assets or liabilities. Due to the complexity of valuing the consideration paid and the purchase price allocation, and the timing of these activities, certain amounts included in the unaudited condensed consolidated financial statements, including long-lived assets, deferred taxes, and goodwill, are provisional and subject to additional adjustments within the measurement period as permitted by Topic 805. In the third quarter of 2021, we recorded a measurement-period adjustment of $0.5 million to reduce the value of intangible assets acquired with a corresponding offset to goodwill. The adjustment did not have a material impact on the amortization expense recorded in the previous quarters.

The following summarizes the provisional estimated fair values of the assets acquired and liabilities assumed at the date of acquisition for the Optelian Acquisition (in thousands):

Provisional allocation of purchase consideration
Cash and cash equivalents	$	1,236		$	1,236
Accounts receivable - trade		460			460
Other receivables		153			153
Inventories		448			448
Prepaid expenses and other current assets		49			49
Property, plant and equipment		718			718
Intangible assets		3,630			3,160
Accounts payable - trade		(390	)		(390	)
Contract liabilities		(169	)		(169	)
Accrued and other liabilities		(123	)		(123	)
Goodwill		1,478			1,948
Total purchase consideration	$	7,490		$	7,490

The provisional purchase price allocation resulted in the recognition of goodwill of approximately ~~$1.5~~$1.9 million. The following table represents the preliminary estimated fair value and useful lives of identifiable intangible assets acquired (estimated fair value in thousands):

Estimated

fair value

useful life

fair value

useful life

Intangible assets acquired

Developed technology

2,250

5 years

1,780

5 years

Customer relationships

500

5 years

490

5 years

In-process research and development

880

5 years

890

5 years

Total intangible assets

3,630

3,160

There were no material differences between total revenue and net loss reported and pro forma total revenues and pro forma net loss that would have been reported for the financial periods presented.

On March 3, 2021, the Company acquired substantially all of the assets of RIFT, Inc., a network automation solutions company, and all the outstanding shares of RIFTIO India Private Limited, a wholly owned subsidiary of RIFT, Inc. (collectively “RIFT”). RIFT developed a carrier-grade RIFT.ware software platform that simplifies the deployment of any slice, service, or application on any cloud. The total purchase consideration was $0.5 million, including a $0.2 million holdback that was released in April of 2021 following the fulfillment of certain requirements in the purchase agreement. The Company allocated the purchase price to $0.1 million in net tangible assets, $0.2 million in developed technologies, and $0.2 million in goodwill. As a result of the acquisition, RIFTIO India Private Limited became a wholly owned subsidiary of the Company.

The Company utilizes a fair value hierarchy that is intended to increase consistency and comparability in fair value measurements and related disclosures. The fair value hierarchy is based on inputs to valuation techniques that are used to measure fair value that are either observable or unobservable. Observable inputs reflect assumptions market participants would use in pricing an asset or liability based on market data obtained from independent sources while unobservable inputs reflect a reporting entity’s pricing based upon their own market assumptions. The fair value hierarchy consists of the following three levels:

~~The following financial instruments are not measured~~Assets and Liabilities Measured at ~~fair value~~Fair Value on the Company’s unaudited condensed consolidated balance sheet as of March 31, 2021 and December 31, 2020 but require disclosure of their fair values: cash and cash equivalents, restricted cash, accounts and other receivables, accounts payable, accrued liabilities, lease liabilities and debt. a Recurring Basis:

The carrying values of financial instruments such as cash and cash equivalents, restricted cash, accounts and other receivables, accounts payable and accrued liabilities approximate their fair values based on their short-term nature.

The ~~carrying~~Company classifies its contingent liability within Level 3 as it includes inputs not observable in the market. The Company estimates the fair value of contingent consideration as the present value of the ~~Company's lease~~expected contingent payments, determined using the revenue forecast for certain Optelian products through the end of 2023. The fair value of contingent liability is generally sensitive to changes in the revenue forecast. Refer to Note 2 Business Combinations for further information.

The following tables present information about the Company’s assets and liabilities that are measured at fair value on a recurring basis using the above input categories (in thousands):

The change in fair value of the Company’s contingent liability is included in selling, marketing, general and ~~debt approximates~~administrative expenses on the unaudited condensed consolidated statement of comprehensive income (loss). The following table reconciles the beginning and ending balances of the Company’s Level 3 contingent liability (in thousands):

In conjunction with the restructuring in Hanover, Germany and the headquarters relocation to Plano, Texas, we wrote down certain long-lived assets held and used to their fair ~~values based on~~value of $0.2 million, resulting in an impairment charge of $4.5 million, which was included in earnings for the ~~current rates available~~period. The impaired long-lived assets primarily consisted of right-of-use assets, and we used estimated sub-lease payment data to fair value the ~~Company for debt of similar terms and maturities.~~respective assets. We concluded that this fair value measurement should be categorized within Level 2.

As of ~~March 31,~~September 30, 2021 and December 31, 2020, the Company's cash, cash equivalents and restricted cash consisted of financial deposits. Cash, cash equivalents and restricted cash held within the U.S. are held at FDIC insured depository institutions. Cash, cash equivalents and restricted cash held outside the U.S. totaled ~~$28.3~~$22.3 million and $32.2 million as of ~~March 31,~~September 30, 2021 and December 31, 2020, respectively. Restricted cash consisted primarily of cash restricted for performance bonds, warranty bonds and collateral for borrowings. Long-term restricted cash was $0.2 million as of ~~March 31,~~September 30, 2021 and December 31, 2020 and is included in other assets on the unaudited condensed consolidated balance sheets.

Balance sheet detail as of ~~March 31,~~September 30, 2021 and December 31, 2020 is as follows (in thousands):

	March 31, 2021		December 31, 2020		September 30, 2021		December 31, 2020
Raw materials	$	20,662	$	16,962	$	33,012	$	16,962
Work in process		1,128		1,486		832		1,486
Finished goods		19,326		21,124		24,426		21,124
Total inventories	$	41,116	$	39,572	$	58,270	$	39,572

Inventories are stated at the lower of cost or net realizable value, with cost being computed based on an adjusted standard basis, which approximates actual cost on an average or first-in, first-out basis. The Company had 0 inventories provided as collateral for borrowings from Export-Import Bank of Korea as of ~~March 31,~~September 30, 2021 compared to $9.6 million as of December 31, 2020.

	March 31, 2021			December 31, 2020			September 30, 2021			December 31, 2020
Property, plant and equipment, net:
Machinery and equipment	$	13,863		$	13,656		$	13,866		$	13,656
Leasehold improvements		4,993			4,633			5,202			4,633
Computers and software		2,835			2,829			3,133			2,829
Furniture and fixtures		1,538			1,123			1,685			1,123
Other		934			716
Construction in progress and other								2,386			716
		24,163			22,957			26,272			22,957
Less: accumulated depreciation and amortization		(15,973	)		(15,445	)		(16,794	)		(15,445	)
Less: government grants		(310	)		(366	)		(222	)		(366	)
Total property, plant and equipment, net	$	7,880		$	7,146		$	9,256		$	7,146

Depreciation expense associated with property, plant and equipment for the three and nine months ended ~~March 31,~~September 30, 2021 was $0.7 million and ~~March 31,~~$2.3 million, respectively. Depreciation expense associated with property, plant and equipment for the three and nine months ended September 30, 2020 was ~~$0.9~~$0.6 million and ~~$0.5~~$1.6 million, respectively.

The Company receives grants from certain foreign government entities mainly to support capital expenditures in the region. Such grants are deferred and are generally refundable to the extent the Company does not utilize the funds for qualifying

expenditures. Once earned, the Company records the grants as a contra amount to the assets and amortizes such amount over the useful lives of the related assets as a reduction to depreciation expense.

The Company accrues warranty costs based on historical trends for the expected material and labor costs to provide warranty services. The Company's standard warranty period is one year from the date of shipment with the ability for customers to purchase an extended warranty of up to five years from the date of shipment. The following table summarizes the activity related to the product warranty liability:

	March 31,						Nine Months Ended September 30,
	2021			2020			2021			2020
Balance at the beginning of the quarter	$	1,522		$	1,610
Balance at the beginning of the period							$	1,522		$	1,610
Charged to cost of revenue		269			33			636			341
Claims and settlements		(267	)		(495	)		(745	)		(1,026	)
Foreign exchange impact		56			(37	)		68			(15	)
Balance at the end of the quarter	$	1,580		$	1,111
Balance at the end of the period							$	1,481		$	910

The Company records contract assets when it has a right to consideration and records accounts receivable when it has an unconditional right to consideration. Contract liabilities consist of cash payments received (or unconditional rights to receive cash) in advance of fulfilling performance obligations. The majority of the Company's performance obligations in its contracts with customers relate to contracts with duration of less than one year.

The opening and closing balances of current and long-term contract assets and contract liabilities related to contracts with customers are as follows:

	Contract assets		Contract liabilities			Contract assets			Contract liabilities
December 31, 2020	$	6,182	$	6,871		$	6,182		$	6,871
March 31, 2021		6,233		6,492
September 30, 2021							3,466			7,536
Increase (decrease)	$	51	$	(379	)	$	(2,716	)	$	665

The ~~increase~~decrease in contract assets during the ~~three~~nine months ended ~~March 31,~~September 30, 2021 was primarily due to ~~revenue recognition criteria being met for items not yet invoiced during the period.~~invoicing that occurred in 2021 from unbilled balances reflected as contract assets as of December 31, 2020.

The ~~decrease~~increase in contract liabilities during the ~~three~~nine months ended ~~March 31,~~September 30, 2021 was primarily due to ~~the revenue recognition criteria~~amounts being ~~met~~invoiced for ~~previously deferred revenue, partially offset by invoiced amounts~~certain customers that did not yet meet the revenue recognition criteria. The amount of revenue recognized in the ~~three~~nine months ended ~~March 31,~~September 30, 2021 that was included in the prior period contract liability balance was ~~$2.1~~$3.6 million. This revenue consists of services provided to customers who had been invoiced prior to the current year. We expect to recognize approximately 61% of outstanding contract liabilities as revenue over the next 12 months and the remainder thereafter.

The balance of contract cost deferred as of ~~March 31,~~September 30, 2021 and December 31, 2020 was ~~$0.4 million and~~ $0.5 million, respectively. During the ~~three~~nine months ended ~~March 31,~~September 30, 2021, the Company recorded $0.4 million in amortization related to contract cost deferred as of December 31, 2020.

~~As of March 31, 2021 and December 31, 2020, the net carrying value of goodwill is all attributable to the Company’s Americas reporting unit.~~

During the ~~three~~nine months ended ~~March 31,~~September 30, 2021, the Company recorded goodwill of ~~$1.5~~$1.9 million related to the acquisition of Optelian and $0.2 million related to the acquisition of ~~RIFT.~~RIFT, which was allocated to the Americas reporting unit. Refer to Note 2 Business Combinations for further information. The accumulated impairment of goodwill was $1.0 million as of ~~March 31,~~both September 30, 2021 and ~~2020, respectively.~~2020.

	March 31, 2021							September 30, 2021
	Gross Carrying Amount		Accumulated Amortization			Net		Gross Carrying Amount		Accumulated Amortization			Net
Developed technology	$	5,477	$	(2,885	)	$	2,592	$	5,007	$	(3,371	)	$	1,636
Customer relationships		5,740		(2,421	)		3,319		5,730		(2,730	)	$	3,000
In-process research and development		880		(32	)		848		890		(118	)	$	772
Total intangible assets, net	$	12,097	$	(5,338	)	$	6,759	$	11,627	$	(6,218	)	$	5,409
	December 31, 2020
	Gross Carrying Amount		Accumulated Amortization			Net
Developed technology	$	3,060	$	(2,652	)	$	408
Customer relationships		5,240		(2,271	)		2,969
Total intangible assets, net	$	8,300	$	(4,923	)	$	3,377

During the ~~three~~nine months ended ~~March 31,~~September 30, 2021, the Company recorded ~~$2.4~~$1.9 million, $0.5 million and $0.9 million in developed technology, customer relationships and in-process research and development, respectively, related to the acquisitions of Optelian and RIFT. Refer to Note 2 Business Combinations for further information.

The following table summarizes the activity related to intangible assets, net (in thousands):

Amortization expense associated with intangible assets for the ~~three~~nine months ended ~~March 31,~~September 30, 2021 and 2020 was ~~$0.4~~$1.3 million and ~~$0.8~~$2.3 million, respectively.

The following table presents the future amortization expense of the Company’s intangible assets as of ~~March 31,~~September 30, 2021 (in thousands):

~~The principal balance~~As of ~~the term loan is due to mature in~~September 30, 2021, the Company had 0 debt obligations. During the first half of 2021, the Company paid off the outstanding balance of debt with related parties, foreign banks and other lending institutions. The Company has no ~~other~~ contractual principal payments due in the next five years.

The following tables summarize the Company’s debt as of the beginning of the period (in thousands):

~~Certain~~During prior periods, certain of the Company's foreign subsidiaries ~~have~~ entered into financing arrangements with foreign banks and other lending institutions consisting primarily of revolving lines of credit, trade facilities, term loans and export development loans. These facilities are renewed as they mature and are generally secured by a security interest in certain assets of the applicable foreign subsidiaries and supported by guarantees given by Dasan Networks, Inc. (“DNI”), the Company’s largest stockholder, or third parties. Payments under such facilities are made in accordance with the lender’s amortization schedules, as applicable.

As of ~~March 31, 2021 and~~ December 31, 2020, the Company had an aggregate outstanding balance of ~~$1.8 million and~~ $13.8 million ~~respectively,~~ under such financing arrangements. The weighted average borrowing rates as of ~~March 31, 2021 and~~ December 31, 2020 ~~were 0.0% and~~was 1.8%~~, respectively. The maturity dates and interest rates per annum applicable to~~. During the first two quarters of 2021, the Company paid the entire outstanding ~~borrowings~~balance under ~~these~~such financing ~~arrangements are listed in the tables below (amount in thousands).~~

arrangements. As of ~~March 31,~~September 30, 2021, the Company had 0 borrowings outstanding from banks and other lending institutions.

As of December 31, 2020, the Company had ~~0 outstanding borrowings~~$19.0 million available to draw under ~~the Company's $17.6 million~~its letter of credit facilities with NongHyup Bank and Korea Development Bank. These letter of credit facilities expired in the third quarter of 2021.

During prior periods, certain ~~foreign banks.~~ of the Company's subsidiaries entered into term loan arrangements with DASAN Networks, Inc. (“DNI”). As of ~~March 31, 2021 and~~ December 31, 2020, the Company had ~~$17.6~~an aggregate outstanding balance of $29.8 million ~~and $19.0 million, respectively, available to draw~~ under ~~its credit facilities.~~

such financing arrangements. In ~~February 2016,~~ the ~~Company borrowed $1.8 million from~~ ~~DNI~~ ~~for capital investment with an interest rate~~first quarter of ~~4.6% per annum, payable annually. In January~~ 2021, the entire outstanding balance on ~~this~~these term ~~loan~~loans was repaid.

In March 2018, the Company borrowed KRW 6.5 billion ($5.8 million USD) from DNI of which KRW 5.0 billion ($4.5 million USD) was repaid in August 2018. In February 2021, the remaining outstanding balance on this term loan was repaid.

In December 2018, the Company entered into a Loan Agreement with DNI for a $6.0 million term loan with an interest rate of 4.6% per annum. In January 2021, the entire outstanding balance on this term loan was repaid.

On March 5, 2020, the Company entered into a loan transaction with DNI in the amount of KRW 22.4 billion ($18.5 million USD) with an interest rate of 4.6% per annum. In February 2021, the entire outstanding balance on this term loan was repaid.

Interest expense on related party borrowings was $0.1 million and ~~$0.2~~$0.8 million for the ~~three~~nine months ended ~~March 31,~~September 30, 2021 and 2020, respectively. As of ~~March 31,~~September 30, 2021, the Company had 0 borrowings outstanding from related parties.

On February 27, 2019, the Company entered into a Revolving Credit, Term Loan, Guaranty and Security Agreement with PNC Bank, National Association (“PNC”) and Citibank, N.A. as lenders, and PNC as agent for the lenders (the “PNC Credit Facilities”).

On March 26, 2020, the Company paid the outstanding term loan borrowings in full and terminated the PNC Credit Facilities. In association with this debt repayment, the Company recorded a loss on extinguishment of debt of $1.4 million during the three months ended March 31, 2020.

In the U.S., the Company maintains a 401(k) plan for its employees whereby eligible employees may contribute up to a specified percentage of their earnings, on a pretax basis, subject to the maximum amount permitted by the Internal Revenue Code. Under the 401(k) plan, the Company made discretionary contributions to the plan in 2021. For the three and nine months ended ~~March 31,~~September 30, 2021, the Company recorded an expense of $0.1 million and $0.4 million, respectively, compared to 0 expense for the three and nine months ended ~~March 31,~~September 30, 2020.

The Company maintains a defined contribution plan for its employees in Korea. Under the defined contribution plan, the Company contributes the equivalent of 8.3% of an employee's gross salary into the plan. For ~~both~~ the three months ended ~~March 31,~~September 30, 2021 and September 30, 2020, the Company recorded an expense of $0.3 ~~million.~~million and $0.4 million, respectively. For the nine months ended September 30, 2021 and September 30, 2020, the Company recorded an expense of $0.9 million and $1.0 million, respectively.

The Company sponsors defined benefit plans for its employees in Germany and Japan. Defined benefit plans provide pension benefits based on compensation and years of service. The Germany plans were frozen as of September 30, 2003 and have not been offered to new employees after that date. The Company has recorded the underfunded status as of ~~March 31,~~September 30, 2021 and December 31, 2020, respectively, as a long-term liability on the unaudited condensed consolidated balance sheets. The accumulated benefit obligation for the plans in Germany and Japan was ~~$18.9~~$18.7 million and $20.1 million as of ~~March 31,~~September 30, 2021 and December 31, 2020, respectively.

Periodic benefit costs for the three months ended September 30, 2021 and 2020 were ~~as follows (in thousands):~~$0.1 million, respectively. Periodic benefit costs for the nine months ended September 30, 2021 and 2020 were $0.2 million, respectively.

The Company holds life insurance contracts, with the Company as beneficiary, in the amount of $3.3 million as of ~~March 31,~~September 30, 2021 and $3.5 million as of December 31, 2020, respectively, related to individuals under the pension plans. These insurance contracts are classified as other assets on the Company’s unaudited condensed consolidated balance sheet. The Company intends to use any proceeds from these policies to fund the pension plans. However, since the Company is the beneficiary on these policies, these assets have not been designated pension plan assets.

For the nine months ended September 30, 2021, the Company incurred restructuring and other charges of approximately $12.1 million mainly related to DZS GmbH. The restructuring and other charges consisting of termination-related benefits of $8.5 million, an impairment of long-lived assets charge of $2.7 million mainly related to right-of-use assets from operating leases, professional services of $0.8 million, and $0.1 million of other charges. The termination-related benefits are comprised of statutory benefits of $2.0 million and one-time severance obligations of $6.5 million.

On March 8, 2021, the Company made the strategic decision to transition DZS GmbH to a sales and research and development center by the end of 2021.

On July 15, 2021, the Company came to an agreement with the works council and entered into a social plan that covers statutory benefits and one-time severance obligations. The Company accounted for the statutory benefit obligations in accordance with ASC 712, Nonretirement Postemployment Benefits, and recognized an expense when probable and estimable. The Company accounted for the one-time severance in accordance with ASC 420, Exit or Disposal Cost Obligations, and recognized the expense when the final terms of the benefit arrangement were communicated to the affected employees. The Company incurred restructuring and other charges of approximately ~~$6.3~~$6.6 million and $11.8 million for the three and nine months ended ~~March 31,~~September 30, 2021, respectively, consisting primarily of termination-related benefits.

In May 2021, the Company made the strategic decision to relocate manufacturing function of Optelian to Seminole, Florida and eliminate redundant workforces. The Company incurred restructuring and other charges of approximately $0.3 million for the nine months ended September 30, 2021, consisting primarily of ~~severance and other termination related benefits of $3.5 million, an impairment charge of $2.5 million related to right-of-use assets from operating leases, and $0.3 million of other charges.~~

Negotiations are being held with the works council in Germany on a reconciliation of interests and a social plan. The Company expects to incur additional severance and other termination benefits when negotiations are finalized.

~~The following table summarizes the activity related to the accrued restructuring~~termination-related benefits. NaN such costs ~~for~~were incurred during the three months ended ~~March 31,~~September 30, 2021.

the Company had $7.4 million of accrued liabilities related to the restructuring costs.

As of ~~March 31,~~September 30, 2021, the Company had 0 outstanding borrowings from related parties compared to $29.8 million as of December 31, 2020. See Note 7 Debt for further information about the Company’s related party debt.

The following table sets forth payment guarantees of the Company's ~~indebtedness and other~~ obligations as of ~~March 31,~~September 30, 2021 that have been provided by DNI. DNI owns approximately ~~37.5%~~37.1% of the outstanding shares of the Company's common stock. The amount guaranteed exceeds the principal amounts of outstanding obligations due to collateral requirements by the banks.

Guarantor	Amount Guaranteed (in thousands)		Description of Obligations Guaranteed	Amount Guaranteed (in thousands)		Description of Obligations Guaranteed
DNI	$	8,400	Credit facility with Industrial Bank of Korea		6,077	Payment guarantee to Industrial Bank of Korea
DNI		6,000	Credit facility with NongHyup Bank		1,621	Payment guarantee to Shinhan Bank
DNI		8,400	Credit facility with Korea Development Bank
DNI		2,206	Payment guarantee to Industrial Bank of Korea
DNI		3,000	Payment guarantee to Shinhan Bank
	$	28,006		$	7,698

Sales, cost of revenue, ~~manufacturing (included in cost of revenue),~~ research and product development, selling, marketing, general and administrative, interest expense and other expenses to and from related parties were as follows (in thousands) for the three and nine months ended ~~March 31,~~September 30, 2021 and 2020:

		Three Months Ended March 31, 2021														Three Months Ended September 30, 2021
Counterparty	DNI ownership interest	Sales		Cost of revenue		Manufacturing (cost of revenue)**		Research and product development		Selling, marketing, general and administrative		Interest expense		Other expenses		Sales		Cost of revenue		Research and product development		Selling, marketing, general and administrative		Interest expense		Other expenses
DNI	N/A	$	1,770	$	1,611	$	—	$	—	$	707	$	132	$	85	$	54	$	45	$	253	$	394	$	—	$	42
Dasan Invest*	N/A		—		—		10		46		18		—		—		—		10		43		19		—		—
		$	1,770	$	1,611	$	10	$	46	$	725	$	132	$	85	$	54	$	55	$	296	$	413	$	—	$	42

		Three Months Ended March 31, 2020														Three Months Ended September 30, 2020
Counterparty	DNI ownership interest	Sales		Cost of revenue		Manufacturing (cost of revenue)**		Research and product development		Selling, marketing, general and administrative		Interest expense		Other expenses		Sales		Cost of revenue		Research and product development		Selling, marketing, general and administrative		Interest expense		Other expenses
DNI	N/A	$	162	$	133	$	—	$	—	$	571	$	151	$	86	$	552	$	485	$	306	$	523	$	324	$	93
Dasan Invest*	N/A		—		—		8		33		38		—		—
		$	162	$	133	$	8	$	33	$	609	$	151	$	86	$	552	$	485	$	306	$	523	$	324	$	93

** Manufacturing costs represent product purchases from and manufacturing activities performed by related parties, and

~~are included in cost of revenue on the unaudited condensed consolidated statement of comprehensive income (loss).~~

The Company has entered into sales agreements with DNI ~~and~~to sell certain ~~of its subsidiaries. Sales~~services and ~~cost of revenue to DNI represent~~ finished goods produced by the ~~Company that are sold to DNI.~~

Company. The Company also has an agreement with DNI in which DNI acts as a sales channel to third party customers. The above transactions are included in sales and cost of revenue on the unaudited condensed consolidated statement of comprehensive income (loss). Sales to DNI are recorded net of royalty fees ~~in related party revenue.~~for a sales channel arrangement.

DNS California shares human resources, treasury and other administrative support with DNI. As such, the Company entered into certain service sharing agreements with DNI and certain of its subsidiaries for the shared office space and shared administrative services.

DNS Korea ~~entered into~~has two separate ~~sublease~~lease agreements with ~~DNI.~~DNI related to the lease of office space and warehouse facilities. Operating lease cost related to these leases totaled ~~$0.5 million and~~ $0.4 million for ~~the~~ three months ended ~~March 31,~~September 30, 2021 and 2020, respectively. Operating lease cost related to these leases totaled $1.3 million for the nine months ended September 30, 2021 and 2020, respectively. Operating lease expense is allocated between cost of revenue, research and product development, and selling, marketing, general and administrative expenses on the unaudited condensed consolidated statement of comprehensive income (loss).As of ~~March 31,~~September 30, 2021, the ~~right of use~~right-of-use asset and operating lease liability related to these leases were ~~$7.8 million and $7.8 million, respectively.~~$6.7 million. As of December 31, 2020, the ~~right of use~~right-of-use asset and operating lease liability related to these leases were $8.6 ~~million and $8.6 million, respectively.~~million.

The Company has ~~entered into~~ an agreement with Dasan Invest to provide IT services for the Company. The respective expense is allocated between cost of revenue, research and product development, and selling, marketing, general and administrative expenses on the unaudited condensed consolidated statement of comprehensive income (loss).

Interest expense represents interest paid to DNI for the related party debt. Refer to Note 7 Debt for further information.

Other expenses ~~to related parties~~ represent expenses to DNI for its payment guarantees relating to the Company's borrowings. The Company pays DNI a guarantee fee which is calculated as 0.9% of the guaranteed amount. Refer to ~~Note 14 Commitments and Contingencies~~the table above for further information about obligations guaranteed by DNI.

Balances of receivables and payables arising from sales and purchases of goods and services with related parties as of ~~March 31,~~September 30, 2021 and December 31, 2020 were included in the following balance sheet captions on the unaudited condensed consolidated balance sheets, as follows (in thousands):

		As of March 31, 2021										As of September 30, 2021
Counterparty	DNI ownership interest	Account receivables		Other receivables		Other assets		Loans Payable		Accounts payable		Account receivables		Other receivables		Other assets		Loans Payable		Accounts payable
DNI	N/A	$	1,912	$	—	$	940	$	—	$	596	$	106	$	215	$	693	$	—	$	564
Dasan Invest*	N/A		—		—		—		—		27		—		—		—		—		26
		$	1,912	$	—	$	940	$	—	$	623	$	106	$	215	$	693	$	—	$	590

		As of December 31, 2020										As of December 31, 2020
Counterparty	DNI ownership interest	Account receivables		Other receivables		Other assets		Loans Payable		Accounts payable		Account receivables		Other receivables		Other assets		Loans Payable		Accounts payable
DNI	N/A	$	2,278	$	247	$	755	$	29,754	$	1,552	$	2,278	$	247	$	755	$	29,754	$	1,552
Dasan Invest*	N/A		—		—		—		—		32		—		—		—		—		32
		$	2,278	$	247	$	755	$	29,754	$	1,584	$	2,278	$	247	$	755	$	29,754	$	1,584

On January 26, 2021, the Company sold 4.6 million shares of common stock (including 0.6 million shares issued pursuant to the underwriters’ option to purchase additional shares) at a price of $14.00 per share in an underwritten public offering. The equity offering closed on January 29, 2021 and resulted in gross proceeds to the Company of approximately $64.4 million and net proceeds to the Company, after deducting underwriting discounts and commissions and offering expenses, of approximately $59.5 million. The Company used a portion of the net proceeds from the equity offering to pay off the remaining outstanding balance of debt with related ~~parties.~~parties.

Basic net income (loss) per share is computed by dividing the net income (loss) for the period by the weighted average number of shares of common stock outstanding during the period. The calculation of diluted net income (loss) per share gives effect to common stock equivalents; however, potential common stock equivalents are excluded if their effect is antidilutive. Potential common stock equivalents are composed of incremental shares of common stock issuable upon the exercise of stock options and the vesting of restricted stock units. In periods when a net loss is reported, all common stock equivalents are excluded from the calculation because they would have an anti-dilutive effect, meaning the loss per share would be reduced. Therefore, in periods when a loss is reported, basic and dilutive loss per share are the same.

The following table is a reconciliation of the numerator and denominator in the basic and diluted net income (loss) per share calculation (in thousands, except per share data) for the three and nine months ended ~~March 31,~~September 30, 2021 and 2020:

	Three Months Ended March 31,						Three months ended September 30,						Nine months ended September 30,
	2021			2020			2021			2020			2021			2020
Net income (loss)	$	(23,225	)	$	(8,771	)	$	(5,896	)	$	(115	)	$	(32,400	)	$	(9,042	)
Weighted average number of shares outstanding:
Basic		25,252			21,474			27,201			21,592			26,484			21,532
Effect of dilutive securities:
Stock options, restricted stock units and share awards		—			—			—			—			—			—
Diluted		25,252			21,474			27,201			21,592			26,484			21,532
Net income (loss) per share:
Basic	$	(0.92	)	$	(0.41	)	$	(0.22	)	$	(0.01	)	$	(1.22	)	$	(0.42	)
Diluted	$	(0.92	)	$	(0.41	)	$	(0.22	)	$	(0.01	)	$	(1.22	)	$	(0.42	)

The following table sets forth potential common stock that is not included in the diluted net income (loss) per share calculation above because their effect would be anti-dilutive for the periods indicated (in thousands):

The Company leases certain properties and buildings (including manufacturing facilities, warehouses, and office spaces) and equipment under various arrangements which provide the right to use the underlying asset and require lease payments for the lease term. The Company’s lease portfolio consists of operating leases which expire at various dates through 2028.

In August 2020, the Company completed its relocation of its corporate headquarters from ~~Oakland,~~Alameda, California to Plano, Texas and ~~establish~~established a new U.S.-based Engineering Center of Excellence in Plano. In September 2020, the Company entered into a lease agreement for additional office space at its headquarters in Plano, ~~TX.~~Texas. On the commencement date of this lease in March 2021, the Company recognized an aggregate of approximately $1.7 million in right-of-use assets and operating lease liabilities in connection with these leases.

During the ~~three~~nine months ended ~~March 31,~~September 30, 2021, the Company recorded $4.2 million in impairment charges on ~~ROU~~the right-of-use assets, including $2.5 million related to the restructuring in Hanover, Germany and $1.7 million related to ~~consolidating certain non-manufacturing facilities into our new~~the headquarters ~~facility in~~relocation to Plano, Texas. See Note 9 Restructuring and Other Charges for further information about the Company's restructuring activities in Hanover, Germany.

	Three Months Ended March 31,				Three months ended September 30,				Nine months ended September 30,
	2021		2020		2021		2020		2021		2020
Operating lease cost	$	1,362	$	1,410	$	952	$	1,335	$	3,301	$	4,024
Short-term lease cost		197		36		382		252		1,146		752
Total net lease cost	$	1,559	$	1,446	$	1,334	$	1,587	$	4,447	$	4,776

Variable lease cost was 0t significant for the three and nine months ended ~~March 31,~~September 30, 2021 and 2020.

Supplemental cash flow information related to the Company’s operating leases was as follows (in thousands):

	Three Months Ended March 31,				Three months ended September 30,				Nine months ended September 30,
	2021		2020		2021		2020		2021		2020
Operating cash outflows from operating leases	$	1,391	$	1,403	$	1,923	$	1,357	$	4,690	$	3,903
ROU assets obtained in exchange for operating lease obligations	$	1,800	$	26
Right-of-use assets obtained in exchange for operating lease obligations						409		—		2,283		1,364

The following table presents the weighted average remaining lease term and weighted average discount rates related to the Company’s operating leases as of ~~March 31,~~September 30, 2021 and December 31, 2020, ~~respectively:~~respectively (in thousands, excluding years and percentages):

The following table presents the maturity of the Company’s operating lease liabilities as of ~~March 31,~~September 30, 2021 (in thousands):

Remainder of 2021	$	4,076		$	1,701
2022		5,235			4,877
2023		4,814			4,442
2024		4,330			3,866
2025		2,579			2,531
Thereafter		2,457			2,457
Total operating lease payments		23,491			19,874
Less: imputed interest		(2,902	)		(3,062	)
Total operating lease liabilities	$	20,589		$	16,812

In the normal course of operations, from time to time, the Company arranges for the issuance of various types of performance bonds, such as performance, warranty, and bid bonds, in the form of bank guarantees or surety bonds. These instruments are arrangements under which the financial institution or surety provides a financial guarantee that the Company will perform in accordance with contractual or legal obligations. As of ~~March 31,~~September 30, 2021, the Company had ~~$10.5~~$7.6 million of performance bonds in the form of bank guarantees or surety bonds guaranteed by third parties.

The Company has, as part of the Optelian purchase agreement, a contingent liability payable to the sellers. The contingent consideration is payable based on the achievement of certain future performance targets during the three-year period following the acquisition date. The Company records changes in the fair value of contingent consideration liabilities within operating expenses in the unaudited condensed consolidated statement of operations during the period in which a change in the estimate of fair value is made. Refer to Note 2 Business Combinations for further information.

From time to time, the Company is subject to various legal proceedings, claims and litigation arising in the ordinary course of business. While the outcome of these matters is currently not determinable, the Company records an accrual for legal contingencies that it has determined to be probable to the extent that the amount of the loss can be reasonably estimated. The Company does not expect that the ultimate costs to resolve these matters will have a material adverse effect on its consolidated financial position, results of operations or cash flows. However, litigation is subject to inherent uncertainties, and unfavorable rulings could occur. If an unfavorable ruling were to occur, there exists the possibility of a material adverse impact on the results of operations and cash flows of the reporting period in which the ruling occurs, or future periods.

Income tax expense for the three and nine months ended ~~March 31,~~September 30, 2021 was approximately ~~$0.9~~$0.7 million and $2.0 million respectively, on pre-tax loss of ~~$22.3 million. There was no income~~$5.2 million and pre-tax loss of $30.4 million, respectively. Income tax expense for the three and nine months ended ~~March 31,~~September 30, 2020 was approximately $1.6 million and $2.5 million respectively, on pre-tax income of $1.5 million and pre-tax loss ~~of $8.8 million.~~$6.6 million, respectively.

As of ~~March 31,~~September 30, 2021, the income tax rate varied from the United States statutory income tax rate primarily due to valuation allowances in North America and EMEA and taxable income generated by the Company’s wholly owned foreign subsidiaries in Asia.

The total amount of unrecognized tax benefits, including interest and penalties, at ~~March 31,~~September 30, 2021 was $1.3 million. There were 0 significant changes to unrecognized tax benefits during the ~~three~~nine months ended ~~March 31,~~September 30, 2021. The Company does not anticipate any significant changes with respect to unrecognized tax benefits within the next twelve months.

The Company is a global provider of ultra-broadband network access solutions and communications platforms deployed by advanced Tier 1, national and regional service providers and enterprise customers. There are no segment managers who are held accountable for operations, operating results and plans for levels or components below the Company unit level. Accordingly, the Company is considered to be in a single ~~reporting segment and~~ operating ~~unit structure.~~segment. The Company’s chief operating decision maker is the Company’s Chief Executive Officer, who reviews financial information presented on a consolidated basis accompanied with disaggregated revenues by geographic region for purposes of making operating decisions and assessing financial performance.

The Company attributes revenue from customers to individual countries based on location shipped. Refer to Note 1(e) Disaggregation of Revenue for the required disclosures on geographical concentrations and revenues by source.

The Company's property, plant and equipment, net of accumulated depreciation, were located in the following geographical areas (in thousands) as of ~~March 31,~~September 30, 2021 and December 31, 2020:

	March 31, 2021		December 31, 2020		September 30, 2021		December 31, 2020
United States	$	3,594	$	2,878	$	5,406	$	2,878
Korea		2,294		2,472		2,172		2,472
Japan		870		952		844		952
Canada		619		—		400		—
Germany		412		761		337		761
Other		91		83		97		83
	$	7,880	$	7,146	$	9,256	$	7,146

Item 2.Management’s Discussion and Analysis of Financial Condition and Results of Operations

As used in this Quarterly Report on Form 10-Q, unless the context suggests otherwise, the terms “DZS,” the “Company” “we,” “our” and “us” refer to DZS Inc. and its subsidiaries.

This Quarterly Report on Form 10-Q, including “Management’s Discussion and Analysis of Financial Condition and Results of Operations,” contains forward-looking statements regarding future events and our future results that are subject to the safe harbors created under the Securities Act of 1933 (the “Securities Act”) and the Securities Exchange Act of 1934 (the “Exchange Act”). These statements are based on current expectations, estimates, forecasts, and projections about the industries in which we operate, and reflect the beliefs and assumptions of our management as of the date hereof.

We use words such as “anticipate,” “believe,” “continue,” “could,” “estimate,” “expect,” “forecast,” “goal,” “intend,” “may,” “plan,” “project,” “seek,” “should,” “target,” “will,” “would,” variations of such words, the negative of such words, and similar expressions to identify forward-looking statements. In addition, statements that refer to projections of earnings, revenue, costs or other financial items in future periods; our ability to satisfy our short- and long-term cash requirements; anticipated growth and trends in our business, industry or key markets; future growth and revenues from our products; our plans and our ability to refinance or repay our existing indebtedness prior to the applicable maturity dates; our ability to access other capital to fund our future operations; future economic conditions and performance; the impact of the global outbreak of COVID-19; the impact of interest rate and foreign currency fluctuations; ~~the impact of the completed relocation of our corporate headquarters to Texas;~~ anticipated performance of products or services; competition; plans, objectives and strategies for future operations, including our pursuit or strategic acquisitions and our continued investment in research and development; other characterizations of future events or circumstances; and all other statements that are not statements of historical fact, are forward-looking statements within the meaning of the Securities Act and the Exchange Act. Although we believe that the assumptions underlying the forward-looking statements are reasonable, we can give no assurance that our expectations will be attained. Factors which could have a material adverse effect on our operations and future prospects or which could cause actual results to differ materially from our expectations include, but are not limited to:

You are urged to consider these factors carefully in evaluating the forward-looking statements herein and are cautioned not to place undue reliance on such forward-looking statements, which are qualified in their entirety by this cautionary statement.

We are a global provider of packet-based mobile transport, broadband access, network orchestration and cloud-native automation solutions deployed by advanced Tier I, national and regional service providers and enterprise customers. Our solutions are deployed worldwide. Our intelligent-edge solutions are focused on creating significant value for our customers by delivering innovative solutions that empower global communication advancement by shaping the internet connection experience.

We research, develop, test, sell, manufacture and support platforms in the areas of mobile transport and fixed broadband access, as discussed below. We have extensive regional development and support centers around the world to support our customer needs.

Our network access solutions and communications platforms include products in Mobile Transport and Fixed Broadband Access, which includes broadband access and connected premises.

~~In addition, we have our~~ ~~DZS Cloud portfolio~~ ~~and our~~ ~~DZS Helix portfolio~~. DZS Cloud accelerates our software capabilities specifically in the areas of network orchestration, application slicing, automation, analytics, and service assurance. Communications service providers are implementing software defined networking (“SDN”) and network functions virtualization (“NFV”) architectures to reduce reliance on proprietary systems and hardware, which increase service agility, flexibility, and deployment of new network services while lowering costs. DZS Helix is our connected premises product portfolio, offering a large collection of smart gateway platforms for any FTTx deployment.

On March 8, 2021, we made the strategic decision, subject to the proper involvement of the employee representatives, to transition DZS GmbH to a sales and research and development center. Negotiations are being held with the works council in Germany on a reconciliation of interests and a social plan. DZS GmbH is expecting to reduce headcount by approximately 100 employees.

~~On March 3, 2021, we acquired substantially all of the assets of RIFT, Inc., a software defined orchestration, automation and network slicing provider.~~

On February 5, 2021, we acquired Optelian Access Networks Corporation, a leading optical networking solution provider based in Ottawa, Ontario, Canada, and its portfolio of optical transport solutions.

On January 26, 2021, we issued 4.6 million shares of common stock in an underwritten public offering pursuant to an underwriters’ agreement (including 0.6 million shares issued pursuant to the underwriters’ option to purchase additional shares) at a price of $14.00 per share. The equity offering closed on January 29, 2021 and resulted in gross proceeds of approximately $64.4 million and net proceeds, after deducting underwriting discounts and commissions and offering expenses, of approximately $59.5 million. We used a portion of the net proceeds from the equity offering to pay off the entire outstanding balance of debt with related parties.

We list in the table below the unaudited condensed consolidated statement of ~~comprehensive~~ (loss) income as a percentage of total net revenue for the periods indicated.

	Three Months Ended March 31,						Three months ended September 30,						Nine months ended September 30,
	2021			2020			2021			2020			2021			2020
Net revenue		100	%		100	%		100	%		100	%		100	%		100	%
Cost of revenue		65	%		66	%		64	%		70	%		65	%		68	%
Gross profit		35	%		34	%		36	%		30	%		35	%		32	%
Operating expenses:
Research and product development		14	%		21	%		13	%		10	%		14	%		13	%
Selling, marketing, general and administrative		39	%		28	%		22	%		18	%		28	%		21	%
Restructuring and other charges		8	%		—			8	%		—			5	%		—
Impairment of long-lived assets		2	%		—			—			—			1	%		—
Amortization of intangible assets		1	%		1	%		—			—			—			—
Total operating expenses		64	%		50	%		43	%		28	%		48	%		34	%
Operating income (loss)		(29	)%		(16	)%		(7	)%		2	%		(13	)%		(2	)%
Interest income		—			—			—			—			—			—
Interest expense		—			(1	)%		—			—			—			(1	)%
Loss on extinguishment of debt		—			(3	)%		—			—			—			—
Other income (expense), net		1	%		2	%		1	%		—			1	%		—
Income (loss) before income taxes		(28	)%		(18	)%		(6	)%		2	%		(12	)%		(3	)%
Income tax provision (benefit)		1	%		—			1	%		2	%		1	%		1	%
Net income (loss)		(29	)%		(18	)%		(7	)%		—			(13	)%		(4	)%

	Three Months Ended March 31,									Three months ended September 30,										Nine months ended September 30,
	2021		2020		Increase/ (Decrease)		% change			2021		2020		Increase/ (Decrease)			% change			2021		2020		Increase/ (Decrease)		% change
Products	$	76.2	$	42.7	$	33.5		78.5	%	$	82.9	$	88.9	$	(6.0	)		(6.7	)%	$	237.1	$	197.8	$	39.3		19.9	%
Services		4.8		4.8		—		0.4	%
Services and other										$	5.5	$	5.0		0.5			10.0	%	$	15.1	$	14.1		1.0		7.1	%
Total	$	81.0	$	47.5	$	33.5		70.7	%	$	88.4	$	93.9	$	(5.5	)		(5.9	)%	$	252.2	$	211.9	$	40.3		19.0	%

For the three months ended ~~March 31,~~September 30, 2021, product revenue decreased by 6.7% or $6.0 million to $82.9 million from $88.9 million in the same period last year. The decrease in product revenue during the period was primarily attributable to the very strong prior year results for our mobile transport products. For the three months ended September 30, 2021, service and other revenue of $5.5 million increased by 10.0% partly due to increased product sales.

For the nine months ended September 30, 2021, product revenue increased by ~~78.5%~~19.9% or ~~$33.5~~$39.3 million to ~~$76.2~~$237.1 million from ~~$42.7~~$197.8 million in the same period last year. The increase in product revenue during the period was primarily attributable to increased sales of our mobile transport and fixed broadband ~~projects~~connectivity products and partly as a result of recovering from the impacts of the COVID-19 pandemic in the first half of 2020. For the nine months ended September 30, 2021, service and other revenue of $15.1 million increased by 7.1% partly due to increased product sales.

The following table presents our revenues by geographical concentration (in millions):

From a geographical perspective, the decrease in net revenue for the three months ended September 30, 2021 was attributable to decreased revenue in Asia primarily attributable to the very strong prior year results. The increase in net revenue for the nine

months ended September 30, 2021 was attributable to increased revenue in all regions driven by our enhanced go-to-market strategy and recovery from the impacts of the early onset of the COVID-19 pandemic in the first quarter of 2020. ~~For the three months ended March 31, 2021, service revenue of $4.8 million was consistent with the same period last year.~~

~~The following table presents our revenues by geographical concentration (in millions):~~

From a geographical perspective, the increase in net revenue for the three months ended March 31, 2021 was attributable to increased revenue in all regions and was partly attributed to impacts from the worldwide COVID-19 pandemic in the first quarter of 2020. In addition, the increase in Asia was also attributable to increased revenue related to next generation mobile edge access transport and fixed broadband access solutions.

For the three months ended ~~March 31,~~September 30, 2021, two customers accounted for 15% and 11% of net revenue, respectively. For the nine months ended September 30, 2021, two customers accounted for 18% and ~~10%~~12% of net revenue, respectively. For the three months ended ~~March 31,~~September 30, 2020, two customers accounted for ~~14%~~23% and ~~10%~~12% of net revenue, respectively. For the nine months ended September 30, 2020, one customer accounted for 16% of net revenue.

We anticipate that our results of operations in any given period may depend to a large extent on sales to a small number of large customers. As a result, our revenue for any quarter may be subject to significant volatility based upon changes in orders from one or a small number of key customers.

Total cost of revenue ~~increased 68.1%~~decreased 14.5% to ~~$52.9~~$56.2 million for the three months ended ~~March 31,~~September 30, 2021, compared to ~~$31.5~~$65.8 million for ~~March 31,~~the three months ended September 30, 2020. Total cost of revenue was 63.6% of net revenue for the three months ended September 30, 2021, compared to 70.0% of net revenue for the three months ended September 30, 2020, which resulted in an increase in gross profit percentage to 36.4% for the three months ended September 30, 2021 from 30.0% for the three months ended September 30, 2020. The decrease in total cost of revenue was primarily due to the change in number and mix of products sold, including the geographic mix of those sales.

Total cost of revenue increased 14.4% to $164.8 million for the nine months ended September 30, 2021, compared to $144.0 million for the nine months ended September 30, 2020. Total cost of revenue was 65.3% of net revenue for the ~~three~~nine months ended ~~March 31,~~September 30, 2021, compared to ~~66.3%~~67.9% of net revenue for the ~~three~~nine months ended ~~March 31,~~September 30, 2020, which resulted in an increase in gross profit percentage to 34.7% for the ~~three~~nine months ended ~~March 31,~~September 30, 2021 from ~~33.7%~~32.1% for the ~~three~~nine months ended ~~March 31,~~September 30, 2020. The increase in total cost of revenue was primarily due to the increase in number and mix of products sold, including the geographic mix of those sales.

We expect that in the future our cost of revenue as a percentage of net revenue will vary depending on the geographic and product mix and average selling prices of products sold. In addition, continued competitive and economic pressures could cause us to reduce our prices, adjust the carrying values of our inventory, or recognize inventory expenses relating to discontinued products and excess or obsolete inventory.

Research and product development expenses include personnel costs, outside contractor and consulting services, depreciation on lab equipment, costs of prototypes and overhead allocations.

Research and product development expenses increased by ~~14.5%~~29.6% to ~~$11.1~~$11.7 million for the three months ended ~~March 31,~~September 30, 2021 compared to ~~$9.7~~$9.0 million for the three months ended ~~March 31, 2020, mainly~~September 30, 2020. Research and product development expenses increased by 27.7% to $34.8 million for the nine months ended September 30, 2021 compared to $27.2 million for the nine months ended September 30, 2020. The increase in research and product development expenses was primarily due to strategic hiring decisions in research, development, and product line management in the second half of 2020 and into the first ~~quarter~~half of 2021 with the intent to accelerate growth and capture market share.

We intend to continue to invest in research and product development to attain our strategic product development objectives, while seeking to manage the associated costs through expense controls.

Selling, marketing, general and administrative expenses include personnel costs for sales, marketing, administration, finance, information technology, human resources and general management as well as legal and accounting expenses, rent, utilities, trade show expenses and related travel costs.

Selling, marketing, general and administrative expenses increased ~~$18.3 million or 135.6%~~by 16.3% to ~~$31.8~~$19.5 million for the three months ended ~~March 31,~~September 30, 2021 compared to ~~$13.5~~$16.8 million for the three months ended ~~March 31,~~September 30, 2020. The increase was due to strategic hiring decisions across sales and administration in the second half of 2020 and into the first half of 2021 with the intent to accelerate growth and capture market share, along with the full quarter impact of the Optelian and Rift acquisitions.

Selling, marketing, general and administrative expenses increased by 60.1% to $69.6 million for the nine months ended September 30, 2021 compared to $43.5 million for the nine months ended September 30, 2020.The increase in selling, marketing, general and administrative expenses was primarily due to the increase in allowance for doubtful accounts for one customer in India by $14.2 ~~million.~~million in the first quarter of 2021. Refer to Note 1 in the Notes to Unaudited Condensed Consolidated Financial Statements, for further information on the bad debt expense. The increase was also partially due to strategic hiring decisions across sales and administration in the second half of 2020 and into the first ~~quarter~~half of 2021 with the intent to accelerate growth and capture market ~~share.~~share, along with the impact of the Optelian and Rift acquisitions.

Restructuring and other charges for the nine months ended September 30, 2021 were $12.1 million and relate primarily to the strategic decision to transition DZS GmbH to a sales and research and development center by the end of 2021. During July 2021, the Company and works council agreed to the terms of and entered into a social plan that included employee termination benefits in conjunction with the restructuring in Germany. The Company accounted for the one-time employee termination benefits when the final terms of the benefit arrangement were communicated to the affected employees in the third quarter of 2021, as reflected in the increase to restructuring and other charges in the statement of operations during the three months ended ~~March 31,~~September 30, 2021 ~~was $6.3 million, and relate to the restructuring activities related to Hanover, Germany.~~of $6.7 million. See Note 9 Restructuring and Other Charges of the Notes to Unaudited Condensed Consolidated Financial Statements included in this Quarterly Report on Form 10-Q for further information.

Impairment of long-lived assets for the ~~three~~nine months ended ~~March 31,~~September 30, 2021 was $1.7 million, and ~~relates~~related to the ~~consolidation of office space in~~headquarters relocation to Plano, Texas. No impairment was recorded during the ~~United States.~~three months ended September 30, 2021. See Note 13 Leases of the Notes to Unaudited Condensed Consolidated Financial Statements included in this Quarterly Report on Form 10-Q for further information.

Income tax expense for the three and nine months ended ~~March 31,~~September 30, 2021 was ~~$0.9~~$0.7 million and $2.0 million, respectively, on pre-tax loss of ~~$22.3 million. There was no income~~$5.2 million and $30.4 million, respectively. Income tax expense for the three and nine months ended ~~March 31,~~September 30, 2020 was $1.6 million and $2.5 million, respectively, on pre-tax income of $1.5 million and pre-tax loss of ~~$8.8 million.~~ $6.6 million, respectively. For the three and nine months ended ~~March 31,~~September 30, 2021, the effective income tax rate varied from the United States statutory income tax rate primarily due to valuation allowances in North America and EMEA and the mix of earnings generated by our wholly owned foreign subsidiaries in Asia.

In managing our business and assessing our financial performance, we supplement the information provided by our U.S. GAAP results with adjusted earnings before stock-based compensation, interest, taxes, and depreciation, or Adjusted EBITDA, a non-U.S. GAAP financial measure. We define Adjusted EBITDA as net income (loss) plus (i) interest expense, net, (ii) provision (benefit) for taxes, (iii) depreciation and amortization, (iv) stock-based compensation, and (v) the impact of material transactions or events that we believe are not indicative of our core operating performance, such as acquisition costs, goodwill impairment, impairment of long-lived assets, loss on debt extinguishment, restructuring and other charges, headquarters relocation, executive transition, and bad debt expense related to a large customer in India, any of which may or may not be recurring in nature. We believe that the presentation of Adjusted EBITDA enhances the usefulness of our financial information by presenting a measure that management uses internally to monitor and evaluate our operating performance and to evaluate the effectiveness of our business strategies. We believe Adjusted EBITDA also assists investors and analysts in comparing our performance across reporting periods on a consistent basis because it excludes the impact of items that we do not believe reflect our core operating performance.

Adjusted EBITDA has limitations as an analytical tool. Some of these limitations are:

Because of these limitations, Adjusted EBITDA should not be considered in isolation or as a substitute for net income (loss) or any other performance measures calculated in accordance with U.S. GAAP or as a measure of liquidity. Management understands these limitations and compensates for these limitations by relying primarily on our U.S. GAAP results and using Adjusted EBITDA only as a supplemental measure.

Set forth below is a reconciliation of net income (loss) to Adjusted EBITDA, which we consider to be the most directly comparable U.S. GAAP financial measure to Adjusted EBITDA (in thousands):

	Three Months Ended March 31,						Three months ended September 30,						Nine months ended September 30,
	2021			2020			2021			2020			2021			2020
Net income (loss)	$	(23,225	)	$	(8,771	)	$	(5,896	)	$	(115	)	$	(32,400	)	$	(9,042	)
Add (deduct):
Interest expense, net		207			573			29			432			245			1,405
Income tax provision (benefit)		893			(5	)		676			1,619			2,032			2,452
Depreciation and amortization		1,265			1,256			1,112			1,386			3,555			3,935
Stock-based compensation		1,352			782			3,104			1,660			6,450			3,310
Headquarters relocation		1,920			—
Headquarters and facilities relocation								(908	)		35			1,012			35
Restructuring and other charges		6,252			—			6,754			—			12,098			—
Acquisition costs		643			—			9			—			689			—
Executive transition		71			—			200			1,383			372			1,383
Bad debt expense*		14,206			—			—			—			14,206			-
Loss on debt extinguishment		—			1,369			—			—			—			1,369
Adjusted EBITDA	$	3,584		$	(4,796	)	$	5,080		$	6,400		$	8,259		$	4,847

* See Note 1 of the Notes to Unaudited Condensed Consolidated Financial Statements included in this Quarterly Report on Form 10-Q for further information.

For a complete description of what we believe to be the critical accounting policies and estimates used in the preparation of our unaudited condensed consolidated financial statements, refer to Note 1 Organization and Summary of Significant Accounting Policies in the notes to our audited consolidated financial statements in our Annual Report on Form 10-K for the year ended December 31, 2020, as supplemented by Note 1 Organization and Summary of Significant Accounting Policies in the notes to our unaudited condensed consolidated financial statements in Part I, Item 1 of this Quarterly Report on Form 10-Q.

Our operations are financed through a combination of our existing cash, cash equivalents, available credit facilities, and sales of equity and debt instruments, based on our operating requirements and market conditions.

The following table summarizes the information regarding our cash and cash equivalents and working capital (in thousands):

	March 31, 2021		December 31, 2020		September 30, 2021		December 31, 2020
Cash and cash equivalents	$	56,818	$	45,219	$	45,505	$	45,219
Working capital		130,713		123,285		121,780		123,285

WeThe Company had a net loss of ~~$23.2~~$5.9 million and $32.4 million for the three months and nine months ended ~~March 31,~~September 30, 2021, ~~and~~respectively. The Company had a net loss of ~~$8.8~~$0.1 million and $9.0 million for the three months and nine months ended ~~March 31, 2020.~~September 30, 2020, respectively.

As of ~~March 31,~~September 30, 2021, we had ~~an accumulated deficit of $75.5 million and~~ working capital of ~~$130.7~~$121.8 million. As of ~~March 31,~~September 30, 2021, we had ~~$56.8~~$45.5 million in cash and cash equivalents, which included ~~$26.3~~$22.3 million in cash balances held by our international ~~subsidiaries, and $1.8 million in aggregate principal debt.~~subsidiaries.

On January 29, 2021, we closed an equity offering which resulted in gross proceeds of approximately $64.4 million and net proceeds, after deducting underwriting discounts and commissions and offering expenses, of approximately $59.5 million. We used a portion of the net proceeds from the equity offering to pay off the outstanding balance of debt with financial institutions and related parties.

We continue to focus on cost management, operating efficiency and efficient discretionary spending. In addition, if necessary, we may sell assets, issue debt or equity securities or purchase credit insurance. We may also rationalize the number of products we sell, adjust our manufacturing footprint, and reduce our operations in low margin regions, including reductions in headcount. Based on our current plans and current business conditions, we believe that these measures along with our existing cash and cash equivalents will be sufficient to satisfy our anticipated cash requirements for at least the next 12 months from the date of this Quarterly Report on Form 10-Q.

gatherings, business closures or operating restrictions, social distancing, and shelter-in-place orders. The health effects of the

pandemic and the above measures taken in response thereto have had an effect on the global economy in general and have materially impacted and may continue to impact on our financial condition, results of operations and cash flows. Given the ongoing and dynamic nature of the virus and the worldwide response related thereto, it is difficult to predict the full impact of the COVID-19 pandemic on our business. Due to the uncertainty around the future economic impact of the pandemic, the fair value measurements used in our impairment assessments could be negatively impacted and could result in future impairments of goodwill, intangibles and other long-lived assets. During the ~~three~~nine months ended ~~March 31,~~September 30, 2021, our revenues increased by ~~70.7%~~19.0%, compared to the ~~three~~nine months ended ~~March 31,~~September 30, 2020, however the impact of a continued COVID-19 pandemic or sustained measures taken to limit or contain the outbreak could have a material and adverse effect on our business, financial condition, results of operations, and cash flows.

In 2017, we entered into an agreement with a customer in India to supply product for a state sponsored broadband project. We billed the customer, which is a state government sponsored entity, approximately $59.0 million and collected payments of approximately $41.7 million, leaving a balance of approximately $17.3 million as of December 31, 2020. We substantially completed our obligations under the agreement in 2018, and all amounts due were billed under the terms of the agreement by December 31, 2020. The remaining $17.3 million is substantially beyond the customers contractual payment terms, and we have been actively working with the customer and third parties in India to arrange payment of the entire remaining balance of $17.3 million. We recorded an allowance for doubtful accounts of $3.1 million on December 31, 2020, for a partial payment promised but not received. In late March 2021, the customer’s state government parent experienced difficulty passing a budget further impacting the ability of the customer to make agreed-upon partial payments to us. In light of this recent development in the first quarter of 2021, we recognized an additional allowance of $14.2 million to bring the total allowance for the customer to $17.3 million, which is the total balance as of March 31, 2021. We will continue to pursue collection of the entire outstanding balance and any amounts collected will be recognized in the period which they are received. In the event our efforts to collect from this customer prove unsuccessful, DZS may seek payment through other means, including through legal action.

Net cash used in operating activities increased by ~~$7.5~~$4.1 million to ~~$6.9~~$15.1 million for the ~~three~~nine months ended ~~March 31,~~September 30, 2021 from net cash ~~provided by~~used in operating activities of ~~$0.6~~$11.0 million for the ~~three~~nine months ended ~~March 31,~~September 30, 2020. The increase in cash used in operating activities was primarily due to ~~changes~~restructuring activities related to our Hanover location, an increase in ~~operating assets~~research and ~~liabilities due to increases~~development expenses, along with an increase in ~~inventory~~selling, general and ~~prepaid~~administrative expenses, ~~and other assets,~~ partially offset by ~~decreases~~an increase in ~~accounts payable.~~gross margin. The increase in research and product development expenses was primarily due to strategic hiring decisions in research, development, and product line management in the second half of 2020 and into the first half of 2021 with the intent to accelerate growth and capture market share. The increase in selling, general and administrative expenses was due to strategic hiring decisions across sales and administration in the second half of 2020 and into the first half of 2021 with the intent to accelerate growth and capture market share, along with the impact of the Optelian and Rift acquisitions.

Net cash used in investing activities increased by ~~$4.9~~$6.7 million to ~~$5.5~~$8.6 million for the ~~three~~nine months ended ~~March 31,~~September 30, 2021 from ~~$0.6~~$1.9 million for the ~~three~~nine months ended ~~March 31,~~September 30, 2020. This increase was primarily due to cash used in the Optelian and RIFT acquisitions.

Net cash provided by financing activities totaled ~~$21.3~~$21.6 million for the ~~three~~nine months ended ~~March 31,~~September 30, 2021 and consisted primarily of proceeds from the equity offering of $59.5 million, partially offset by repayments of our short-term borrowings and related party term loan. This is in comparison to cash provided by financing activities of ~~$3.1~~$19.8 million for the ~~three~~nine months ended ~~March 31,~~September 30, 2020 and consisted primarily of proceeds from a related party loan, factored accounts receivable accounted for as a secured borrowing, and proceeds from short-term borrowings, partially offset by a net outflow associated with the repayment of the PNC ~~credit facility.~~Credit Facilities and other short-term borrowings.

Our primary source of liquidity comes from our cash, cash equivalents and restricted cash, which totaled ~~$63.8~~$52.4 million at ~~March 31,~~September 30, 2021. Our cash, cash equivalents and restricted cash as of ~~March 31,~~September 30, 2021 included ~~$28.3~~$22.3 million held by our international subsidiaries.

~~Certain~~As of ~~our foreign subsidiaries have entered into various financing arrangements~~September 30, 2021, we had no outstanding balances with ~~foreign~~ banks and other lending institutions consisting primarily of letter of credit trade facilities, term loans and export development loans. These facilities are renewed on an annual basis and supported by guarantees given by DNI or third parties. Payments under such facilities are made in accordance with the given lender’s amortization schedules.

institutions. As of ~~March 31, 2021 and~~ December 31, 2020, we had an aggregate outstanding balance of ~~$1.8 million and~~ $13.8 million ~~respectively,~~under financing arrangements with foreign banks and other lending institutions. During the first half of 2021, we paid off the outstanding balance of debt under such financing ~~arrangements, and the interest rate per annum applicable to outstanding borrowings under these financing arrangements had an interest rate of zero percent as of March 31, 2021.~~ arrangements.

As of September 30, 2021, we had no related party debt outstanding. As of December 31, 2020, we had an aggregate outstanding balance of $29.8 million of related party debt with DNI. In January and February 2021, we paid off the outstanding balance of debt with related parties with proceeds from the issuance of shares of our common stock during January 2021.

Our fixed commitments for cash expenditures consist primarily of payments under operating leases, and inventory purchase ~~commitments, and payments of principal and interest for debt obligations.~~commitments.

From time to time, we may provide or commit to extend credit or credit support to our customers. This financing may include extending the terms for product payments to customers. Any extension of financing to our customers will limit the capital that we have available for other uses.

Our accounts receivable, while not considered a primary source of liquidity, represent a concentration of credit risk because a significant portion of the accounts receivable balance at any point in time typically consists of a relatively small number of customer account balances. As of ~~March 31,~~September 30, 2021, ~~one customer~~two customers represented ~~19%~~18% and 15% of net accounts receivable, respectively, and net receivables from customers in countries other than the United States represented ~~84%~~80%. We do not currently have any material commitments for capital expenditures, or any other material commitments aside from operating leases for our facilities, and inventory purchase ~~commitments and debt.~~commitments.

Future minimum operating lease obligations include primarily payments for our office locations and manufacturing, research and development locations, which expire at various dates through 2028. See Note 13 Leases of the Notes to Unaudited Condensed Consolidated Financial Statements included in this Quarterly Report on Form 10-Q for further information regarding our operating leases.

We may have short term purchase commitments related to the purchase orders for products and services, within the normal course of business. These arrangements typically have cancellation provisions that allow us to cancel with little to no penalty.

We are required to maintain disclosure controls and procedures designed to provide reasonable assurance of achieving the objective that information required to be disclosed in our reports filed or submitted pursuant to the Exchange Act is recorded, processed, summarized and reported within the time periods specified in the SEC’s rules and forms and that such information is accumulated and communicated to our management, including our principal executive officer and principal financial officer, as appropriate to allow for timely decisions regarding required disclosures. Our disclosure controls and procedures include those components of our internal control over financial reporting intended to provide reasonable assurance that transactions are recorded as necessary to permit preparation of financials in accordance with U.S. GAAP. In designing and evaluating the disclosure controls and procedures, management recognizes that any controls and procedures, no matter how well designed and operated, can provide only reasonable assurance of achieving the desired control objectives, and management applies its judgment in evaluating the cost-benefit relationship of possible controls and procedures.

As required by Rule 13a-15(b) under the Exchange Act, we conducted an evaluation of the effectiveness of our disclosure controls and procedures as of ~~March 31,~~September 30, 2021, the end of the period covered by this Quarterly Report on Form 10-Q. The evaluation was done under the supervision and with the participation of management, including our principal executive officer and principal financial officer. In the course of the evaluation of our disclosure controls and procedures, our principal executive officer and principal financial officer concluded our disclosure controls and procedures were effective as of ~~March 31,~~September 30, 2021.

There were no changes in our internal control over financial reporting that occurred during our last fiscal quarter that have materially affected, or are reasonably likely to materially affect, our internal control over financial reporting.

The Company is subject to various legal proceedings, claims and litigation arising in the ordinary course of business. While the outcome of these matters is currently not determinable, the Company does not expect that the ultimate costs to resolve these matters will have a material adverse effect on the unaudited condensed consolidated financial position or results of operations. However, litigation is subject to inherent uncertainties, and unfavorable rulings could occur. If an unfavorable ruling were to occur, there exists the possibility of a material adverse impact on the financial position, results of operations and cash flows of the period in which the ruling occurs, or future periods.

The exhibits required to be filed with this quarterly report on Form 10-Q are listed in the Exhibit Index attached hereto and are incorporated herein by reference.

Pursuant to the requirements of the Securities Exchange Act of 1934, the registrant has duly caused this report to be signed on its behalf by the undersigned thereunto duly authorized.

Delaware		22-3509099
(State or other jurisdiction of incorporation or organization)		(I.R.S. Employer Identification Number)

5700 Tennyson Parkway, Suite 400 Plano, Texas		75024
(Address of principal executive offices)		(Zip code)

Title of each class	Trading Symbol(s)	Name of each exchange on which registered

Common stock, $0.001 par value	DZSI	The Nasdaq Stock Market LLC

		Page
PART I. FINANCIAL INFORMATION

Item 1.	Financial Statements	3
	Unaudited Condensed Consolidated Balance Sheets	3
	Unaudited Condensed Consolidated Statements of Comprehensive Income (Loss)	4
	Unaudited Condensed Consolidated Statements of Stockholders' Equity	5
	Unaudited Condensed Consolidated Statements of Cash Flows	6
	Notes to Unaudited Condensed Consolidated Financial Statements	7
Item 2.	Management’s Discussion and Analysis of Financial Condition and Results of Operations	22
Item 3.	Quantitative and Qualitative Disclosures About Market Risk	30
Item 4.	Controls and Procedures	30

PART II. OTHER INFORMATION

Item 1.	Legal Proceedings	31
Item 5.	Other Information	31
Item 6.	Exhibits	31
	Signatures	33

Purchase consideration
Retirement of Optelian debt	$	4,929
Payment to shareholders and option holders		664
Contingent payment to shareholders		1,897
Total purchase consideration	$	7,490

	September 30,
		2021			2020
Balance at the beginning of the period, gross	$	4,980		$	4,980
Accumulated impairment at the beginning of the period		(1,003	)		(1,003	)
Goodwill from acquisitions		2,168			-
Balance at the end of the period	$	6,145		$	3,977

Large accelerated filer	☐	Accelerated filer	☒
Non-accelerated filer	☐	Smaller reporting company	☒
		Emerging growth company	☐

	September 30, 2021
	Level 1		Level 2		Level 3		Total
Cash and cash equivalents	$	45,505		-		-	$	45,505
Restricted cash		6,884		-		-		6,884
Contingent liability		-		-		2,116		2,116
Total	$	52,389	$	-	$	2,116	$	54,505

Remainder of 2021	$	1,218
2022		1,283
2023		1,283
2024		1,283
2025		1,283
Thereafter		409
Total	$	6,759

Remainder of 2021	$	294
2022		1,177
2023		1,177
2024		1,177
2025		1,177
Thereafter		407
Total	$	5,409

	March 31, 2021
	Short-term		Long-term		Total
Bank and Trade Facilities - Foreign Operations	$	1,764	$	—	$	1,764
	$	1,764	$	—	$	1,764

	Nine Months Ended September 30, 2021
Counterparty	Sales		Cost of revenue		Research and product development		Selling, marketing, general and administrative		Interest expense		Other expenses
DNI	$	1,965	$	1,791	$	776	$	1,185	$	132	$	180
Dasan Invest*		—		30		134		57		—		—
	$	1,965	$	1,821	$	910	$	1,242	$	132	$	180

	Nine Months Ended September 30, 2020
Counterparty	Sales		Cost of revenue		Research and product development		Selling, marketing, general and administrative		Interest expense		Other expenses
DNI	$	2,077	$	1,887	$	690	$	1,183	$	763	$	263
Dasan Invest*		—		20		81		55		—		—
	$	2,077	$	1,907	$	771	$	1,238	$	763	$	263

	March 31, 2021		March 31, 2020
Outstanding stock options		2,216		1,896
Unvested restricted stock units		744		58

	September 30, 2021			December 31, 2020
Lease Assets and Liabilities
Assets:
Right-of-use assets from operating leases	$	12,932		$	18,483

Liabilities:
Operating lease liabilities - current	$	4,118		$	4,494
Operating lease liabilities - non-current		12,694			15,959
Total operating lease liabilities	$	16,812		$	20,453
Weighted average remaining lease term	4.4 years			4.6 years
Weighted average discount rate		5.5	%		5.7	%

Exhibit Number		Description

3.1		Restated Certificate of Incorporation of DASAN Zhone Solutions, Inc. (incorporated by reference to Exhibit 3.1 to the Company’s Annual Report on Form 10-K filed with the SEC on September 27, 2017).

3.2		Certificate of Amendment to the Restated Certificate of Incorporation of DZS Inc. (incorporated by reference to Exhibit 3.1 to the Company’s Current Report on Form 8-K filed with the SEC on August 27, 2020).

3.3		Amended and Restated Bylaws of DZS Inc. (incorporated by reference to Exhibit 3.2 to the Company’s Annual Report on Form 10-K filed with the SEC on March 11, 2021).

10.1+		Employment Agreement effective August 2, 2021 by and between DZS Inc. and Misty D. Kawecki (incorporated by reference to Exhibit 10.1 to the Company’s Current Report on Form 8-K filed with the SEC on August 2, 2021).

31.1*		Certification of Chief Executive Officer Pursuant to Rule 13a-14(a)/15d-14(a)

31.2*		Certification of Chief Financial Officer Pursuant to Rule 13a-14(a)/15d-14(a)

32.1*		Section 1350 Certification of Chief Executive Officer and Chief Financial Officer

101.INS		Inline XBRL Instance Document – the instance document does not appear in the Interactive Data File because XBRL tags are embedded within the Inline XBRL document

101.SCH		Inline XBRL Taxonomy Extension Schema

101.CAL		Inline XBRL Taxonomy Extension Calculation Linkbase

101.DEF		Inline XBRL Taxonomy Extension Definition Linkbase

101.LAB		Inline XBRL Taxonomy Extension Labels Linkbase

101.PRE		Inline XBRL Taxonomy Extension Presentation Linkbase

104		Cover Page Interactive Data File (embedded within the Inline XBRL document and included in Exhibit 101)

*		Filed herewith.
+		Indicates management contract or compensatory plan, contract or arrangement.

	DZS INC.

Date: ~~May 10,~~November 3, 2021
	By:	/s/ Charles Daniel Vogt
	Name:	Charles Daniel Vogt
	Title:	President and Chief Executive Officer

	By:	/s/ ~~Thomas J. Cancro~~Misty Kawecki
	Name:	~~Thomas J. Cancro~~Misty Kawecki
	Title:	Chief Financial Officer
		(Principal Financial and
		Accounting Officer)