Condensed Consolidated Balance Sheets - USD ($)	Sep. 30, 2021	Dec. 31, 2020
Current Assets:
Cash and cash equivalents	$ 8,841,000	$ 8,824,000
Contract assets	0	92,000
Prepaid expenses	390,000	268,000
Other current assets	65,000	198,000
Total current assets	9,296,000	9,382,000
Fixed assets, net	657,000	427,000
Patents and other intangible assets, net	942,000	1,302,000
Other assets	10,000	10,000
Total Assets	10,905,000	11,121,000
Current Liabilities:
Accounts payable and accrued liabilities	274,000	435,000
Current portion of lease liabilities	202,000	169,000
Accrued compensation and taxes	606,000	382,000
Contract liabilities	0	94,000
Total current liabilities	1,082,000	1,080,000
Long Term Liabilities:
Long term lease liabilities	403,000	249,000
Payroll protection program loan	0	251,000
Total liabilities	1,485,000	1,580,000
Commitments and contingencies (Note 7)
Stockholders' Equity:
Preferred stock, $0.0001 par value, zero shares issued and outstanding	0	0
Common stock, $0.0001 par value, 31,574,704 and 30,077,436 shares issued and outstanding at September 30, 2021 and December 31, 2020, respectively	3,000	3,000
Additional paid-in capital	90,955,000	84,411,000
Accumulated deficit	(81,538,000)	(74,874,000)
Total ClearSign Technologies Corporation stockholders' equity	9,420,000	9,540,000
Noncontrolling Interest	0	1,000
Total stockholders' equity	9,420,000	9,541,000
Total Liabilities and Stockholders' Equity	$ 10,905,000	$ 11,121,000

Carrying value as of the balance sheet date of liabilities incurred (and for which invoices have typically been received) and payable to vendors for goods and services received that are used in an entity's business. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer).

Name:	us-gaap_AccountsPayableCurrent
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Carrying value as of the balance sheet date of obligations incurred and payable, pertaining to costs that are statutory in nature, are incurred on contractual obligations, or accumulate over time and for which invoices have not yet been received or will not be rendered. Examples include taxes, interest, rent and utilities. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer).