During the nine months ended September 30, 2021, the Company transferred $467,600 of instruments previously classified as inventory to property and equipment leased to customers. During the nine months ended September 30, 2020, the Company transferred $232,800 of instruments previously classified as inventory to property and equipment leased to customers.
For the three and nine months ended September 30, 2021, the Company incurred depreciation and amortization expense of $366,000 and $1,007,400, respectively. For the three and nine months ended September 30, 2020, the Company incurred depreciation and amortization expense of $290,300 and $768,500, respectively.
In the three and nine months ended September 30, 2020, the Company capitalized $3,800 and $12,100, respectively, of interest expense related to capitalized software development projects. NaN interest expense was capitalized in the three and nine months ended September 30, 2021.
Deferred Offering Costs
The Company capitalizes certain legal, accounting and other third-party fees that are directly associated with in-process equity financings as deferred offering costs (non-current) until such financings are consummated or determined not to be probable of consummation. After consummation of the equity financing, these costs are recorded in stockholders’ equity as a reduction of proceeds received as a result of the offering. If the equity financing is no longer considered probable of being consummated, all deferred offering costs will be charged to operating expenses in the consolidated statement of operations at such time.
During the third quarter of 2021, the Company netted $17.6 million in issuance costs against IPO proceeds (see Note 2). As of September 30, 2021 and December 31, 2020, there were no capitalized deferred offering costs in the condensed consolidated balance sheets.
Leases
In transactions where the Company is the lessee, at the inception of a contract, the Company determines if the arrangement is, or contains, a lease. See Note 7 for additional details over leases where the Company is the lessee.
All transactions in which the Company is the lessor are short-term (one year or less) and have been classified as operating leases. All leases require upfront payments covering the full period of the lease and thus, there are no future payments expected to be received from existing leases. See Note 3 for details over revenue recognition related to lease agreements.
Loss Per Share
Basic loss per share is computed by dividing net loss available to common stockholders by the weighted average number of shares of common stock outstanding during the period.
For periods of net income, and when the effects are not anti-dilutive, diluted earnings per share is computed by dividing net income available to common stockholders by the weighted-average number of shares outstanding plus the impact of all potential dilutive common shares, consisting primarily of common stock options and stock purchase warrants using the treasury stock method.
For periods of net loss, diluted loss per share is calculated similarly to basic loss per share because the impact of all dilutive potential common shares is anti-dilutive. The number of anti-dilutive shares excluded from the computation of diluted loss per share, consisting of shares underlying stock options, was 13.0 million for the three and nine months ended September 30, 2021. The number of anti-dilutive shares excluded from the computation of diluted loss per share, consisting of shares underlying stock options and stock purchase warrants, was 13.0 million for the three and nine months ended September 30, 2020.