Summary of Significant Accounting Policies	3 Months Ended
Mar. 31, 2021
Accounting Policies [Abstract]
Summary of Significant Accounting Policies	Note 1. Summary of Significant Accounting Policies Basis of Presentation The accompanying condensed consolidated financial statements include Impinj, Inc. and its wholly owned subsidiaries. We have eliminated intercompany balances and transactions in consolidation. We have prepared these condensed consolidated financial statements in conformity with U.S. generally accepted accounting principles, or GAAP, and applicable rules and regulations of the Securities and Exchange Commission, or SEC, regarding interim financial reporting. Certain information and note disclosures normally included in the financial statements prepared in accordance with GAAP have been condensed or omitted pursuant to such rules and regulations. Accordingly, these interim condensed consolidated financial statements should be read in conjunction with the audited consolidated financial statements and accompanying notes as of and for the year ended December 31, 2020 included in Impinj, Inc.’s Annual Report on Form 10-K, which was filed with the SEC on February 17, 2021. The condensed consolidated balance sheet as of December 31, 2020, included herein, was derived from the audited consolidated financial statements of Impinj, Inc. The unaudited condensed consolidated interim financial statements, in the opinion of management, reflect all adjustments, consisting of normal recurring adjustments, necessary to state fairly our financial position, results of operations, and our cash flows for the periods presented. Interim results are not necessarily indicative of the results for a full year or for any other future period. Use of Estimates Preparing financial statements in conformity with GAAP requires us to make certain estimates, judgments and assumptions that affect the reported amounts of assets and liabilities and the related disclosures as of the date of the financial statements, as well as the reported amounts of revenue and expenses during the periods presented. On an ongoing basis, we evaluate our estimates, including those related to revenue recognition, sales incentives, estimates to complete development contracts, deferred revenue, inventory excess and obsolescence, income taxes, determination of the fair value of stock awards and compensation and employee-related benefits. To the extent there are material differences between these estimates, judgments, or assumptions and actual results, our financial statements will be affected. Covid-19 has introduced significant additional uncertainty with respect to estimates, judgments and assumptions about current and forecasted demand, which may materially impact the estimates previously listed, among others. Recently Adopted Accounting Standards In August 2020, the FASB issued guidance on debt with conversion and other options, or ASU 2020-06. This guidance eliminates the beneficial- and cash-conversion accounting models for convertible instruments and amends the derivative scope exception for contracts in an entity’s own equity. Additionally, this guidance requires the application of the “if-converted” method to calculate the impact of convertible instruments on diluted earnings per share. We adopted ASU 2020-06 on January 1, 2021 using the modified retrospective transition method and accounted for our convertible notes due 2026, or the 2019 Notes, on a whole-instrument basis. Upon adoption, we recorded a $29.3 million increase to long-term debt, a $32.7 million decrease to additional paid-in capital and a $3.4 million decrease to accumulated deficit on January 1, 2021. Interest expense decreased for the three months ended March 31, 2021 as we no longer separate an equity component of the 2019 Notes and incurred amortization of debt discount. We had no changes to net deferred tax liabilities with a decrease in deferred tax liability offset by a corresponding increase in valuation allowance upon adoption. We use the “if-converted” method to calculate the impact of convertible instruments on diluted earnings per share for the three months ended March 31, 2021 upon adoption of this guidance. The condensed consolidated financial statements as of and for the three months ended March 31, 2021 are presented under ASU 2020-06, while comparative prior reporting period presented is not adjusted and continue to be reported in accordance with our historical accounting policy. Recently Issued Accounting Standards Not Yet Adopted Recent accounting pronouncements issued by the FASB (including its Emerging Issues Task Force), the American Institute of Certified Public Accountants, and the SEC did not have, or are not expected to have, a material impact on our present or future consolidated financial statements. Accounts Receivable The allowance for doubtful accounts is our best estimate of the amount of probable lifetime-expected credit losses in existing accounts receivable and is determined based on our historical collections experience, age of the receivable, knowledge of the customer and the condition of the general economy and industry as a whole. We record changes in our estimate to the allowance for doubtful accounts through bad debt expense and write off the receivable and corresponding allowance when accounts are ultimately determined to be uncollectible. Bad debt expense is included in general and administrative expenses. For the periods presented in this report, bad debt expense and the allowance for doubtful account were not material. We derive a majority of our accounts receivable from sales to original equipment manufacturers, or OEMs, original design manufacturers, or ODMs, as well as to distributors who are large, well-established companies. We do not have customers that represent a significant credit risk based on current economic conditions and past collection experience. Also, we have not had material past-due balances on our accounts receivable as of March 31, 2021 and December 31, 2020, except for $1.7 million and $1.2 million past-due rent receivables from our sub-lessee as of March 31, 2021 and December 31, 2020, respectively, which we deem collectible based on credit risk of the sub-lessee. Inventory For the three months ended March 31, 2021, sales of fully reserved inventory had a favorable net gross margin impact of 2.2%. These sales, primarily of endpoint IC inventory included in the excess and obsolescence charge for the three months ended March 31, 2020, as noted below, are the result of increased endpoint IC demand in today’s supply-constrained environment. For the three months ended March 31, 2020, we recorded inventory excess and obsolescence charges with an unfavorable net gross margin impact of 5.6%. Those charges, which reduced the inventory value of the impacted products to zero, were due primarily to reduced demand for older-generation endpoint ICs and EU gateways. At the time, we expected future demand to be met by our newer generation endpoint ICs and EU gateways. Instead, as a result of today’s industry-wide wafer shortages, we sold a significant portion of the reserved endpoint ICs in the three months ended March 31, 2021.

Summary of Significant Accounting Policies

3 Months Ended

Mar. 31, 2021

Summary of Significant Accounting Policies

Note 1. Summary of Significant Accounting Policies

Basis of Presentation

The accompanying condensed consolidated financial statements include Impinj, Inc. and its wholly owned subsidiaries. We have eliminated intercompany balances and transactions in consolidation. We have prepared these condensed consolidated financial statements in conformity with U.S. generally accepted accounting principles, or GAAP, and applicable rules and regulations of the Securities and Exchange Commission, or SEC, regarding interim financial reporting. Certain information and note disclosures normally included in the financial statements prepared in accordance with GAAP have been condensed or omitted pursuant to such rules and regulations. Accordingly, these interim condensed consolidated financial statements should be read in conjunction with the audited consolidated financial statements and accompanying notes as of and for the year ended December 31, 2020 included in Impinj, Inc.’s Annual Report on Form 10-K, which was filed with the SEC on February 17, 2021. The condensed consolidated balance sheet as of December 31, 2020, included herein, was derived from the audited consolidated financial statements of Impinj, Inc.

The unaudited condensed consolidated interim financial statements, in the opinion of management, reflect all adjustments, consisting of normal recurring adjustments, necessary to state fairly our financial position, results of operations, and our cash flows for the periods presented. Interim results are not necessarily indicative of the results for a full year or for any other future period.

Use of Estimates

Preparing financial statements in conformity with GAAP requires us to make certain estimates, judgments and assumptions that affect the reported amounts of assets and liabilities and the related disclosures as of the date of the financial statements, as well as the reported amounts of revenue and expenses during the periods presented. On an ongoing basis, we evaluate our estimates, including those related to revenue recognition, sales incentives, estimates to complete development contracts, deferred revenue, inventory excess and obsolescence, income taxes, determination of the fair value of stock awards and compensation and employee-related benefits. To the extent there are material differences between these estimates, judgments, or assumptions and actual results, our financial statements will be affected. Covid-19 has introduced significant additional uncertainty with respect to estimates, judgments and assumptions about current and forecasted demand, which may materially impact the estimates previously listed, among others.

Recently Adopted Accounting Standards

In August 2020, the FASB issued guidance on debt with conversion and other options, or ASU 2020-06. This guidance eliminates the beneficial- and cash-conversion accounting models for convertible instruments and amends the derivative scope exception for contracts in an entity’s own equity. Additionally, this guidance requires the application of the “if-converted” method to calculate the impact of convertible instruments on diluted earnings per share. We adopted ASU 2020-06 on January 1, 2021 using the modified retrospective transition method and accounted for our convertible notes due 2026, or the 2019 Notes, on a whole-instrument basis. Upon adoption, we recorded a $29.3 million increase to long-term debt, a $32.7 million decrease to additional paid-in capital and a $3.4 million decrease to accumulated deficit on January 1, 2021. Interest expense decreased for the three months ended March 31, 2021 as we no longer separate an equity component of the 2019 Notes and incurred amortization of debt discount. We had no changes to net deferred tax liabilities with a decrease in deferred tax liability offset by a corresponding increase in valuation allowance upon adoption. We use the “if-converted” method to calculate the impact of convertible instruments on diluted earnings per share for the three months ended March 31, 2021 upon adoption of this guidance.

The condensed consolidated financial statements as of and for the three months ended March 31, 2021 are presented under ASU 2020-06, while comparative prior reporting period presented is not adjusted and continue to be reported in accordance with our historical accounting policy.

Recently Issued Accounting Standards Not Yet Adopted

Recent accounting pronouncements issued by the FASB (including its Emerging Issues Task Force), the American Institute of Certified Public Accountants, and the SEC did not have, or are not expected to have, a material impact on our present or future consolidated financial statements.

Accounts Receivable

The allowance for doubtful accounts is our best estimate of the amount of probable lifetime-expected credit losses in existing accounts receivable and is determined based on our historical collections experience, age of the receivable, knowledge of the customer and the condition of the general economy and industry as a whole. We record changes in our estimate to the allowance for doubtful accounts through bad debt expense and write off the receivable and corresponding allowance when accounts are ultimately determined to be uncollectible. Bad debt expense is included in general and administrative expenses. For the periods presented in this report, bad debt expense and the allowance for doubtful account were not material.

We derive a majority of our accounts receivable from sales to original equipment manufacturers, or OEMs, original design manufacturers, or ODMs, as well as to distributors who are large, well-established companies. We do not have customers that represent a significant credit risk based on current economic conditions and past collection experience. Also, we have not had material past-due balances on our accounts receivable as of March 31, 2021 and December 31, 2020, except for $1.7 million and $1.2 million past-due rent receivables from our sub-lessee as of March 31, 2021 and December 31, 2020, respectively, which we deem collectible based on credit risk of the sub-lessee.

Inventory

For the three months ended March 31, 2021, sales of fully reserved inventory had a favorable net gross margin impact of 2.2%. These sales, primarily of endpoint IC inventory included in the excess and obsolescence charge for the three months ended March 31, 2020, as noted below, are the result of increased endpoint IC demand in today’s supply-constrained environment.

For the three months ended March 31, 2020, we recorded inventory excess and obsolescence charges with an unfavorable net gross margin impact of 5.6%. Those charges, which reduced the inventory value of the impacted products to zero, were due primarily to reduced demand for older-generation endpoint ICs and EU gateways. At the time, we expected future demand to be met by our newer generation endpoint ICs and EU gateways. Instead, as a result of today’s industry-wide wafer shortages, we sold a significant portion of the reserved endpoint ICs in the three months ended March 31, 2021.