11. Revenue recognition
Net product sales
The Company views its operations and manages its business in one operating segment.
During the three months ended September 30, 2023 and 2022, net product sales outside of the United States were $76.6 million and $79.4 million, respectively, consisting of sales of Translarna, Tegsedi, Waylivra, and Upstaza. Translarna net revenues made up $69.0 million and $76.6 million of the net product sales outside of the United States for the three months ended September 30, 2023 and 2022, respectively. During the three months ended September 30, 2023, and 2022, net product sales in the United States were $67.4 million and $54.8 million, respectively, consisting solely of sales of Emflaza. During the three months ended September 30, 2023, one country, the United States, accounted for at least 10% of the Company’s net product sales, representing $67.4 million of the net product sales. During the three months ended September 30, 2022, two countries, the United States and Russia, accounted for at least 10% of the Company’s net product sales, representing $54.8 million and $28.3 million of the net product sales, respectively. For the three months ended September 30, 2023 and 2022, the Company had a total of three and two distributors, respectively, that each accounted for over 10% of the Company’s net product sales.
During the nine months ended September 30, 2023 and 2022, net product sales outside of the United States were $318.5 million and $247.6 million, respectively, consisting of Translarna, Tegsedi, Waylivra, and Upstaza. Translarna net revenues made up $280.6 million and $232.9 million of the net product sales outside of the United States for the nine months ended September 30, 2023 and 2022, respectively. For the nine months ended September 30, 2023 and 2022, net product sales in the United States were $187.7 million and $160.1 million, respectively, consisting solely of Emflaza. During the nine months ended September 30, 2023, three countries, the United States, Russia, and Brazil, accounted for at least 10% of the Company’s net product sales, representing $187.7 million, $69.0 million, and $52.5 million of net product sales, respectively. During the nine months ended September 30, 2022, two countries, the United States and Russia, accounted for at least 10% of the Company’s net product sales, representing $160.1 million and $57.1 million of net product sales, respectively. For the nine months ended September 30, 2023 and 2022, the Company had a total of two and two distributors, respectively, that each accounted for over 10% of the Company's net product sales.
As of September 30, 2023 and December 31, 2022, the Company does not have a contract liabilities balance related to net product sales, and has not made significant changes to the judgments made in applying ASC Topic 606.
Collaboration and Royalty revenue
In November 2011, the Company and the SMA Foundation entered into the SMA License Agreement with Roche. Under the terms of the SMA License Agreement, Roche acquired an exclusive worldwide license to the Company’s SMA program.
Under the SMA License Agreement, the Company is eligible to receive additional payments from Roche if specified events are achieved with respect to each licensed product, including up to $135.0 million in research and development event milestones, up to $325.0 million in sales milestones upon achievement of specified sales events, and up to double digit royalties on worldwide annual net sales of a commercial product.
The SMA program currently has one approved product, Evrysdi, which was approved in August 2020 by the FDA for the treatment of SMA in adults and children two months and older. As of September 30, 2023, the Company does not have any remaining research and development event milestones that can be received. The remaining potential sales milestones that can be received is $250.0 million.
For the three months ended September 30, 2023, the Company did not recognize collaboration revenue related to the SMA License Agreement with Roche. For the three months ended September 30, 2022, the Company recognized $50.0 million of collaboration revenue related to the SMA License Agreement. For the nine months ended September 30, 2023, the amounts recognized for the collaboration revenue related to the SMA License Agreement with Roche were immaterial. For the nine months ended September 30, 2022, the Company recognized $50.0 million of collaboration revenue related