UNITED STATES SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549

FORM 10-K

[X]

x ANNUAL REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE
SECURITIES EXCHANGE ACT OF 1934

For the fiscal year endedDecember 31, 20172020 or

( )¨   TRANSITION REPORT PURSUANT TO SECTION 13 OR 15 (d) OF THE SECURITIES EXCHANGE ACT OF 1934

      For the transition period from _______ to _______

Commission file number    333-104061-01

BCTC IV ASSIGNOR CORP.
(Exact name of registrant as specified in its charter)

101 Arch Street, 13th Floor Boston, Massachusetts 02110
(Address of principal executive offices)      (Zip Code)

Registrant’s telephone number, including area code (888) 773-1487

One Boston Place, Suite 2100, Boston, Massachusetts 02108
(Address of principal executive offices)      (Zip Code)

Registrant's telephone number, including area code(617)624-8900(Former name, former address and former fiscal year,

if changed since last report)

Securities registered pursuant to Section 12(b) of the Act:

Securities registered pursuant to Section 12(g) of the Act:

Beneficial Assignee Certificates

(Title of Class)

Beneficial Assignee Certificates

Indicate by check mark if the Registrant is a well-known seasoned issuer, as defined in Rule 405 of the Securities Act.

Indicate by check mark if the Registrant is not required to file reports pursuant to Section 13 or Section 15(d) of the Act.

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.

Indicate by check mark whether the registrant has submitted electronically and posted on its corporate Web site, if any, every Interactive Data File required to be submitted and posted 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 and post such files).

Indicate by check mark if disclosure of delinquent filers pursuant to
Item 405 of Regulation S-K (229.405 of this chapter) is not contained
herein, and will not be contained, to the best of registrant's knowledge,
in definitive proxy or information statements incorporated by reference in
Part III of this Form 10-K or any amendment to this Form 10-K. |XX|

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“large accelerated filer," "accelerated” “accelerated filer," "smaller” “smaller reporting company,"” and "emerging“emerging growth company"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 has filed a report on and attestation to its management’s assessment of the effectiveness of its internal control over financial reporting under Section 404(b) of the Sarbanes-Oxley Act (15 U.S.C. 7262(b)) by the registered public accounting firm that prepared or issued its audit report. ¨

Indicate by check mark whether the registrant is a shell company (as defined in Rule 12b-2 of the Exchange Act).

DOCUMENTS INCORPORATED BY REFERENCE

None

BCTC IV ASSIGNOR CORP.

Form 10-K ANNUAL REPORT FOR THE YEAR ENDED DECEMBER 31, 20172020

TABLE OF CONTENTS

PART I

PART II

PART III

PART IV

PART I

PART I

Item 1. Business

Organization

BCTC IV Assignor Corp., a Delaware corporation, is the assignor limited partner (the "Assignor“Assignor Limited Partner"Partner”) was formed for the sole purpose of servingBF Garden Tax Credit Fund IV L.P. (formerly known as an assignor for Boston Capital Tax Credit Fund IV L.P.), a Delaware limited partnership (the "Fund") and willdoes not engage in any other business. Units of beneficial interest in the limited partnership interest of the Assignor Limited Partner will behave been assigned by the Assignor Limited Partner by means of beneficial assignee certificates ("BACs"(“BACs”) to investors and investors will beare entitled to all the rights and economic benefits of a limited partner of the Fund, including rights to a percentage of the income, gains, losses, deductions, credits and distributions of the Fund. The

Effective as of December 15, 2020, BF Garden Companion Limited Partnership, a Massachusetts limited partnership formerly known as Boston Capital Companion Limited Partnership (“Companion”) replaced John P. Manning as the sole owner of the Assignor Limited Partner is wholly-owned by John P. Manning.

Partner. Also effective as of December 15, 2020, BFBC Holdings GP, LLC, a Delaware limited liability company and an affiliate of Boston Financial Investment Management, LP, a Delaware limited partnership (“BFIM”),replaced Boston Capital Partners II Corporation as the general partner of Companion, and BFIM replaced Boston Capital Companion Holdings Limited Partnership as the sole limited partner of Companion.

A Registration Statement on Form S-11 and the related prospectus, as supplemented (the "Prospectus") were filed with the Securities and Exchange Commission and became effective December 16, 1993 in connection with a public offering ("Offering") in one or more series of a minimum of 250,000 BACs and a maximum of 30,000,000 BACs at $10 per BAC. On April 18, 1996 an amendment to Form S-11, which registered an additional 10,000,000 BACs for sale to the public in one or more series, became effective. On April 2, 1998 an amendment to Form S-11, which registered an additional 25,000,000 BACs for sale to the public in one or more series, became effective. On August 31, 1999 an amendment to Form S-11, which registered an additional 8,000,000 BACs for sale to the public became effective. On July 26, 2000 an amendment to Form S-11, which registered an additional 7,500,000 BACs for sale to the public became effective. On July 23, 2001 an amendment to Form S-11, which registered an additional 7,000,000 BACs for sale to the public became effective. On July 24, 2002 an amendment to Form S-S– 11, which registered an additional 7,000,000 BACs for sale to the public became effective. On July 2, 2003, an amendment to Form S-11, which registered an additional 7,000,000 BACs for sale to the public became effective. As of December 31, 2017,2020, subscriptions had been received and accepted by the General Partner in Series 20, Series 21, Series 22, Series 23, Series 24, Series 25, Series 26, Series 27, Series 28, Series 29, Series 30, Series 31, Series 32, Series 33, Series 34, Series 35, Series 36, Series 37, Series 38, Series 39, Series 40, Series 41, Series 42, Series 43, Series 44, Series 45 and Series 46 for 83,651,080 BACs representing capital contributions of $836,177,880.

Description of Business

The Assignor Limited Partner'sPartner’s sole purpose is to act as a conduit through which all of the economic and tax benefits of an investment in the Fund are passed along to the investor BAC holders. The Assignor Limited Partner does not charge any fees for its services and has no income.

The Fund's principal business is to invest as a limited partner in other limited partnerships (the "Operating Partnerships") each of which will own or lease and will operate an apartment complex exclusively or partially for low- and moderate-income tenants. Each Operating Partnership in which the Fund will invest will own apartment complexes which are completed, newly-constructed, under construction or rehabilitation, or to-be constructed or rehabilitated, and which are expected to receive government assistance. Each apartment complex is expected to qualify for the low-income housing tax credit under Section 42 of the Internal Revenue Code (the "Federal Housing Tax Credit"), providing tax benefits over a period of ten to twelve years in the form of tax credits which investors may use to offset income, subject to strict limitations, from other sources. Some apartment complexes may also qualify for the historic rehabilitation tax credit under Section 47 of the Internal Revenue Code (the "Rehabilitation Tax Credit"). Section 236 (f) (ii) of the National Housing Act, as amended, and of the Housing and Urban Development Act of 1965, as amended, each provide for the making by The Department of Housing and Urban Development ("HUD"(“HUD”) of rent supplement payments to low income tenants in properties which receive other forms of federal assistance such as tax credits. The payments for each tenant, which are made directly to the owner of their property, generally are in such amounts as to enable the tenant to pay rent equal to 30% of the adjusted family income. Some of the apartment complexes in which the Fund has invested are receiving such rent supplements from HUD. HUD has been in the process of converting rent supplement assistance to assistance paid not to the owner of the apartment complex, but directly to the individuals. At this time, the Fund is unable to predict whether Congress will continue rent supplement programs payable directly to owners of the apartment complex.

As of December 31, 2017,2020, the Fund has investments in 20 Operating Partnerships on behalf of Series 20, 0 Operating Partnerships on behalf of Series 21, 30 Operating Partnerships on behalf of Series 22, 30 Operating Partnerships on behalf of Series 23, 60 Operating Partnerships on behalf of Series 24, 0 Operating Partnerships on behalf of Series 25, 91 Operating Partnerships on behalf of Series 26, 30 Operating Partnerships on behalf of Series 27, 50 Operating Partnerships on behalf of Series 28, 82 Operating Partnerships on behalf of Series 29, 60 Operating Partnerships on behalf of Series 30, 80 Operating Partnerships on behalf of Series 31, 62 Operating Partnerships on behalf of Series 32, 42 Operating Partnerships on behalf of Series 33, 41 Operating Partnerships on behalf of Series 34, 20 Operating Partnerships on behalf of Series 35, 30 Operating Partnerships on behalf of Series 36, 10 Operating PartnershipPartnerships on behalf of Series 37, 40 Operating Partnerships on behalf of Series 38, 0 Operating Partnerships on behalf of Series 39, 90 Operating Partnerships on behalf of Series 40, 146 Operating Partnerships on behalf of Series 41, 132 Operating Partnerships on behalf of Series 42, 180 Operating Partnerships on behalf of Series 43, 73 Operating Partnerships on behalf of Series 44, 2711 Operating Partnerships on behalf of Series 45 and 1410 Operating Partnerships on behalf of Series 46.

Employees

The Assignor Limited Partner does not have any employees and does not perform any services.

Item 2. Properties

The Assignor Limited Partner has no properties.

Item 3. Legal Proceedings

Item 4. Mine Safety Disclosures

PART II

Item 6. Selected Financial Data

The Assignor Limited Partner has no operational history.

The Assignor Limited Partner has no operational history and capital needs.

PART III

The Assignor Limited Partner'sPartner’s sole shareholder and director, and its executive officers are:

John P. Manning,

Gregory Voyentzie, age 69, is one51, has served as Chief Executive Officer of BFIM since June 2018. Mr. Voyentzie joined BFIM in 1999 and has over 26 years of experience in the affordable housing industry. Prior to his current position, Mr. Voyentzie was an Executive Vice President of BFIM and co-lead of the two original founders of Boston Capital Corporation, which was formed in 1974. From its beginning, Boston Capital's goal was to focus on providing equity investment capitalProduction group, where he maintained joint responsibility for establishing the development of apartment properties throughout the country. Under Mr. Manning's leadership as CEO for the past 44 years, Boston Capital has grown into onestrategic direction of the largest owners/investors in apartment properties in the United States. Through a number of affiliated partnerships, Boston Capital's present portfolio is comprised of approximately 1,556 properties with an original development cost in excess of $18.7 billion. These properties are located in all 50 states, the District of Columbia, Puerto Rico, the U.S. Virgin Islandssyndication platform, identifying and Guam. As CEO of Boston Capital,marketing new capital sources and selecting property-level investments. Mr. Manning continues to oversee the company's business development goals. Capitalizing on its core competencies of tax credit investment underwriting, those business development goals include an expansion of investment capital for market rate real estate investment as well as providing mortgage financing for a limited and exclusive number of property acquisitions. Mr. Manning is a recognized leader in the housing and real estate industries,Voyentzie has held several other senior positions within BFIM and has served on the boards of a number of national housing organizations and governmental commissions. In 1997, President Clinton appointed Mr. Manning to the President's Export Council, a board comprised primarily of Fortune 500 CEOs that advised the President on government policies and programs that affect U.S. trade performance. He was also a Presidential appointee to the President's Advisory Committee on the Arts. Mr. Manning serves on the boards of numerous organizations and charities including The Alliance for Business Leadership and the American Ireland Fund. Mr. Manning is alsobeen a member of the Board of Directors of Liberty Mutual Group, the parent company of Liberty Mutual Insurance Company, and sits on Liberty Mutual's investment and compensation committees. Mr. Manning is a graduate of Boston College.firm's Investment Committee since 2005.

Marc N. Teal,Marie Reynolds, age 54, overseesis the operational accounting, including financialChief Financial Officer (CFO) and SEC reporting, budgeting, auditChief Operating Officer (COO) of BFIM. Ms. Reynolds joined BFIM in 1995 and tax for Boston Capital, its affiliated entities and all Boston Capital-sponsored programs. He is also responsible for the additional oversight of internal audit, regulatory and housing compliance and information technology. Mr. Teal manages Boston Capital's banking and borrowing relationships and directs the treasury management of all working capital reserves. He previously served as Director of Accounting and prior to that served as Vice President of Partnership Accounting. Mr. Teal has more than 2725 years of financefinancial analysis and accounting experience. Priorreporting experience within the affordable housing industry. In her role as CFO and COO of BFIM, Ms. Reynolds sets financial policy for BFIM and works with senior executives to joining Boston Capitalset strategic direction and develop policies that have organization-wide impact. Ms. Reynolds was named BFIM’s CFO in 1990, Mr. Teal held various positions with Cabot, Cabot & Forbes, a multifaceted real estate company2014 and Liberty Real Estate Corp. He received a BSCOO in Accountancy from Bentley University and a Masters in Finance from Suffolk University.

2020.

None

The registrant has no Audit Committee. All audit services and any permitted non-audit services performed by the registrant’s independent auditors are pre-approved by the registrant’s principal executive officer or principal financial officer.

The registrant has no Audit Committee. All audit services and any permitted non-audit services performed by the registrant’s independent auditors are pre-approved by the registrant’s principal executive officer or principal financial officer.

PART IV

BCTC IV Assignor Corp.; filed herein as Exhibit 13 Report of Independent Registered Public Accounting Firm

  Balance Sheets, December 31, 2020 and 2019

  Notes to Balance Sheets, December 31, 2020 and 2019

Schedules not listed are omitted because of the absence of the conditions under which they are required or because the information is included in the financial statements or the notes thereto.

Exhibit No. 3 - Organization Documents.

a. Articles of Incorporation of BCTC IV Assignor Corp.
(Incorporated by reference from Exhibit 3 to the
Fund's Registration Statement No. 33-70564 on Form S-11 as
filed with the Securities and Exchange Commission on October 19,
1993.) (Filed on paper - hyperlink not required pursuant to Rule
105 of Regulation S-T.)


Exhibit No. 10 - Material contracts.

a. Beneficial Assignee Certificate. (Incorporated by reference from
Exhibit 10A to the Fund's Registration Statement No. 33-70564 on
Form S-11 as filed with the Securities and Exchange Commission on
October 19, 1993) (Filed on paper - hyperlink not required
pursuant to Rule 105 of Regulation S-T.)

a. Audited Financial Statement of BCTC IV Assignor Corp. filed herein.

BCTC IV ASSIGNOR CORP 2017 F/S

Exhibit No. 28 - Additional exhibits.

None

SIGNATURES

SIGNATURES

Pursuant to the requirements of Section 13 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.

Pursuant to the requirements of the Securities Exchange Act of 1934,
this report has been signed below by the following persons on behalf of the
registrant and in the capacities and on the dates indicated: