3.	Revenue Recognition

Product Sales

The Company generates revenue from the sale of products, licensing transactions and research and development collaborations. The Company’s product revenues are from the sale of bioprocessing products to customers in the life science and biopharmaceutical industries. Revenue related to product sales is recognized upon delivery of the product to the customer as long as there is persuasive evidence of an arrangement, the sales price is fixed or determinable and collection of the related receivable is reasonably assured. Determination of whether these criteria have been met are based on management’s judgments primarily regarding the fixed nature of the fee charged for the product delivered and the collectability of those fees. The Company has a few longstanding customers who comprise the majority of revenue and have excellent payment histories and therefore the Company does not require collateral. The Company has had no significant write-offs of uncollectible invoices in the periods presented.

At the time of sale, the Company also evaluates the need to accrue for warranty and sales returns. The supply agreements the Company has with its customers and the related purchase orders identify the terms and conditions of each sale and the price of the goods ordered. Due to the nature of the sales arrangements, inventory produced for sale is tested for quality specifications prior to shipment. Since the product is manufactured to order and in compliance with required specifications prior to shipment, the likelihood of sales return, warranty or other issues is largely diminished. Sales returns and warranty issues are infrequent and have had nominal impact on the Company’s financial statements historically.

Orencia Royalty

In April 2008, the Company settled its outstanding litigation with Bristol-Myers Squibb Company (“Bristol”) and began recognizing royalty revenue in fiscal year 2009 for Bristol’s net sales in the United States of Orencia^® which is used in the treatment of rheumatoid arthritis. Pursuant to the settlement with Bristol (“Bristol Settlement”), the Company recognized royalty revenue of approximately $3,846,000 and $3,081,000 for the three months ended March 31, 2013 and 2012, respectively. Revenue earned from Bristol royalties is recorded in the periods when it is earned based on royalty reports sent by Bristol to the Company. The Company has no continuing obligations to Bristol as a result of this settlement. The royalty agreement with Bristol provides that the Company will receive such royalty payments on sales of Orencia^® by Bristol through December 31, 2013.

Pursuant to the Bristol Settlement, Repligen must remit to the University of Michigan 15% of all royalty revenue received from Bristol. Royalty expense for the three months ended March 31, 2013 and 2012 was approximately $577,000 and $462,000, respectively. This operating expense has been included in the Company’s Statements of Operations under the line item “Cost of royalty revenue.”

Pfizer License Agreement

In December 2012, the Company entered into an exclusive worldwide licensing agreement (the “License Agreement”) with Pfizer Inc. (“Pfizer”) to advance the SMA program, which is led by RG3039 and also includes backup compounds and enabling technologies. Under the terms of the License Agreement, the Company received $5 million from Pfizer as an upfront payment on January 22, 2013 and is entitled to receive up to $65 million in potential future milestone payments, a portion of which may be owed to third parties. These potential payments are approximately equally divided between milestones related to clinical development and initial commercial sales in specific geographies. In addition, the Company is entitled to receive royalties on any future sales of RG3039 or any SMA compounds developed under the License Agreement. The royalty rates are tiered and begin in the high single-digits for RG3039 or lesser amounts for any backup compounds developed under the License Agreement. Repligen’s receipt of these royalties is subject to an obligation under an existing in-license agreement and other customary offsets and deductions. There are no refund provisions in this agreement. The Company recognized $4,876,000 of revenue related to the value of the license in the year ended December 31, 2012. The Company recognized $55,000 of revenue in the three months ended March 31, 2013 and expects to recognize the remaining $69,000 of revenue from the upfront payment under the License Agreement in the fiscal quarter ending June 30, 2013 as the Company performs clinical and transition services under the agreement.

Research and Development Agreements

For the three months ended March 31, 2013 and 2012, the Company recognized approximately $621,000 and $401,000 of revenue, respectively, from sponsored research and development projects under agreements with the National Institutes of Health / Scripps Research Institute and Go Friedreich’s Ataxia Research (“GoFar”).

Research revenue is recognized when the expense has been incurred and services have been performed. Determination of which incurred costs qualify for reimbursement under the terms of the Company’s contractual agreements and the timing of when such costs were incurred involves the judgment of management. The Company’s calculations are based on the agreed-upon terms as stated in the arrangements. However, should the estimated calculations change or be challenged by other parties to the agreements, research revenue may be adjusted in subsequent periods. The calculations have not historically changed or been challenged, and the Company does not anticipate any significant subsequent change in its revenue related to sponsored research and development projects.