Revenues
Disaggregated Revenue
The following table presents disaggregated revenue in the following categories (in thousands):
 Years Ended December 31,
20242023
Contract Types:
Licensing$11,297 $3,449 
Engineering and other services19,761 39,196 
Biorefining revenue$31,058 $42,645 
Joint development agreements6,226 8,416 
Contract research4,365 6,233 
Joint development and contract research revenue$10,591 $14,649 
CarbonSmart product7,943 5,337 
Total Revenue
$49,592 $62,631 

The following table presents revenue from partners in collaborative arrangements and from grant contributions which are included in the table above as follows (in thousands):
 Years Ended December 31,
20242023
Revenue from partners in collaborative agreements included in the Joint development agreements above
$5,573 $5,529 
Revenue from grant contributions included in Engineering and other services above
6,403 24,146 
Revenue by Geographic Location
The following table presents disaggregation of the Company’s revenues by customer location for the years ended December 31, 2024 and 2023 (in thousands):
Years Ended December 31,
20242023
North America$23,587 $17,618 
Europe, Middle East, Africa (EMEA)16,260 37,447 
Asia8,862 3,570 
Australia883 3,996 
Total Revenue
$49,592 $62,631 
Contract balances
The following table provides changes in contract assets and liabilities (in thousands):
Current Contract AssetsCurrent Contract LiabilitiesNon-current Contract Liabilities
Balance as of December 31, 2023$28,238 $3,198 $8,233 
Additions to unbilled accounts receivable40,771 — — 
Increases due to consideration received— 15,823 — 
Unbilled accounts receivable recognized in trade receivables(49,934)— — 
Decrease on revaluation on currency(100)(27)(313)
Reclassification from long-term to short-term— 4,030 (4,030)
Reclassification to revenue as a result of performance obligations satisfied— (19,543)— 
Additions due to LanzaJet sublicense
— 2,687 1,343 
Balance as of December 31, 2024$18,975 $6,168 $5,233 
The decrease in contract assets was mostly due to billing certain customers and government entities for engineering and other services that were previously recorded as contract assets. As of December 31, 2024 and December 31, 2023 the Company had $9,456 and $11,157, respectively, of billed accounts receivable, net of allowance.
The increase in current contract liabilities was primarily due to the recognition of the portion of payments in shares received in advance from LanzaJet for the remaining sublicensing performance obligation (refer to Note 6 - Investments for further details), while the decrease in non-current contract liabilities is primarily due to the reclassification to current liabilities for performance obligations that will be completed within one year. The Company expects to recognize the amounts classified as non-current within two to three years.
Remaining performance obligations
Transaction price allocated to the remaining performance obligations represents contracted revenue that has not yet been recognized, including unearned revenue to be recognized in future periods. Transaction price allocated to remaining performance obligations is influenced by factors such as project size, duration, contract modifications, and customer-specific acceptance rights. As of December 31, 2024, the Company had approximately $30,179 in contracted revenue remaining to be recognized, of which $22,329 is expected to be recognized in the next twelve months.

About Revenue Disclosures

Revenue disclosures under ASC 606 explain how a company identifies performance obligations, allocates transaction prices, and determines when revenue is recognized. This section is essential for understanding whether reported revenue reflects genuine economic activity or aggressive accounting choices. Analysts examine the mix of point-in-time versus over-time recognition, which directly affects revenue timing and comparability.

Key signals: rising contract liabilities (deferred revenue) suggest strong future revenue visibility, while declining contract assets may indicate slowing project milestones. Watch for variable consideration estimates — rebates, returns, and performance bonuses that require management judgment. Significant changes in disaggregated revenue by geography or product line can reveal shifting business mix before it appears in headline numbers. Compare revenue growth against contract liability growth to assess sustainability, and scrutinize any changes in the timing of recognition that coincide with earnings pressure.