under this agreement , we may develop these jak inhibitors for the treatment of alopecia areata , or aa , and other dermatological conditions . we paid rigel an upfront nonrefundable payment of $ 8.0 million in 2015 and $ 4.0 million upon the achievement of a specified development milestone in 2019. in addition , we have agreed to make remaining aggregate payments of up to $ 76.0 million upon the achievement of specified development milestones , such as clinical trials and regulatory approvals . further , we have agreed to pay up to an additional $ 10.5 million to rigel upon the achievement of a second set of development milestones . in addition , in connection with the amendment of the agreement in october 2019 , we agreed to pay rigel an amendment fee of $ 1.5 million in three installments of $ 0.5 million in january 2020 , april 2020 and july 2020 , which is included in accrued expenses on our consolidated balance sheet . with respect to any products we commercialize under the rigel license agreement , we will pay rigel quarterly tiered royalties on our annual net sales of each product at a high single digit percentage of annual net sales , subject to specified reductions until the date that all of the patent rights for that product have expired , as determined on a country-by-country and product-by- 61 product basis or , in specified countries under specified circumstances , 10 years from the first commercial sale of such product . the rigel license agreement terminates on the date of expiration of all royalty obligations unless earlier terminated by either party for a material breach . we may also terminate the rigel license agreement without cause at any time upon advance written notice to rigel . rigel , after consultation with us , will be responsible for maintaining and prosecuting the patent rights , and we will have final decision-making authority regarding such patent rights for a product in the united states and the european union . to the extent that we jointly develop intellectual property , we will confer and decide which party will be responsible for filing , prosecuting and maintaining those patent rights . the rigel license agreement also establishes a joint steering committee composed of an equal number of representatives for each party , which will monitor progress in the development of products . stock purchase agreement with vixen pharmaceuticals , inc. and license agreement with columbia university in march 2016 , we entered into a stock purchase agreement , or the vixen agreement , with vixen pharmaceuticals , inc. , or vixen , and jak1 , llc , jak2 , llc and jak3 , llc , or together , the selling stockholders , and shareholder representative services llc as the representative of the selling stockholders . pursuant to the vixen agreement , we acquired all shares of vixen 's capital stock from the selling stockholders , or the vixen acquisition . following the vixen acquisition , vixen became our wholly-owned subsidiary . pursuant to the vixen agreement , we paid $ 0.6 million upfront and issued an aggregate of 159,420 shares of our common stock to the selling stockholders . we are obligated to make annual payments of $ 0.1 million through march 2022 , with such amounts being creditable against specified future payments that may be paid under the vixen agreement . under the vixen agreement we are obligated to make aggregate payments of up to $ 18.0 million to the selling stockholders upon the achievement of specified pre-commercialization milestones for three products covered by the vixen patent rights in the united states , the european union and japan , and aggregate payments of up to $ 22.5 million upon the achievement of specified commercial milestones for products covered by the vixen patent rights . with respect to any covered products that we commercialize under the vixen agreement , we are obligated to pay low single-digit royalties on net sales , subject to specified reductions , limitations and other adjustments , until the date that all of the patent rights for that product have expired , as determined on a country-by-country and product-by-product basis or , in specified circumstances , ten years from the first commercial sale of such product . if we sublicense any of vixen 's patent rights and know-how acquired pursuant to the vixen agreement , we will be obligated to pay a portion of any consideration we receive from such sublicenses in specified circumstances . as a result of the vixen acquisition , we became party to the exclusive license agreement , by and between vixen and the trustees of columbia university in the city of new york , or columbia , dated as of december 31 , 2015 , or , as amended , the columbia license agreement . under the columbia license agreement , we are obligated to pay columbia an annual license fee of $ 10,000 subject to specified adjustments for patent expenses incurred by columbia and creditable against any royalties that may be paid under the columbia license agreement . we are also obligated to pay up to an aggregate of $ 11.6 million upon the achievement of specified commercial milestones , including specified levels of net sales of products covered by columbia patent rights and or know-how , and royalties at a sub-single-digit percentage of annual net sales of products covered by columbia patent rights and or know-how , subject to specified adjustments . if we sublicense any of columbia 's patent rights and know-how acquired pursuant to the columbia license agreement , we will be obligated to pay columbia a portion of any consideration received from such sublicenses in specified circumstances . story_separator_special_tag we recognize revenue when collection of the consideration we are entitled to under a contract with a customer is probable . at contract inception , we assess the goods or services promised within a contract with a customer to identify the performance obligations , and to determine if they are distinct . we recognize revenue that is allocated to each distinct performance obligation when ( or as ) that performance obligation is satisfied . we only recognize revenue when collection of the consideration we are entitled to under a contract with a customer is probable . product sales , net we recognized revenue from product sales at the point the customer obtained control , which generally occurred upon delivery . we also included estimates of variable consideration in the same period revenue was recognized . components of variable consideration included trade discounts and allowances , product returns , government rebates , discounts and rebates , other incentives such as patient co-pay assistance , and other fee for service amounts . variable consideration was recorded on the consolidated balance sheet as either a reduction of accounts receivable , if payable to a customer , or as a current liability , if payable to a third-party other than a customer . we considered all relevant information when estimating variable consideration such as contractual and statutory requirements , specific known market events and trends , industry data and forecasted customer buying and payment patterns . the amount of net revenue that can be recognized is constrained by estimates of variable consideration which are included in the transaction price . payment terms with customers did not exceed one year and , therefore , we did not account for a financing component in our arrangements . we expensed incremental costs of obtaining a contract with a customer , including sales commissions , when incurred as the period of benefit was less than one year . trade discounts and allowances - we provided customers with trade discounts , rebates , allowances and or other incentives . we recorded estimates for these items as a reduction of revenue in the same period the revenue was recognized . government and payor rebates – we contracted with , or were subject to arrangements with , certain third-party payors , including pharmacy benefit managers and government agencies , for the payment of rebates with respect to utilization of our commercial products . we also entered into agreements with gpos that provided for administrative fees and discounted pricing in the form of volume-based rebates . we were also subject to discount and rebate obligations under state medicaid programs and medicare . we recorded estimates for these discounts and rebates as a reduction of revenue in the same period the revenue was recognized . 67 other incentives – we maintained a co-pay assistance program which was intended to provide financial assistance to qualified commercially-insured patients with prescription drug co-payments required by third-party payors . we estimated and recorded accruals for these incentives as a reduction of revenue in the period the revenue was recognized . our estimated amounts for co-pay assistance were based upon the number of claims and the cost per claim that we expected to receive associated with product that had been sold to customers but remained in the distribution channel at the end of each reporting period . product returns - consistent with industry practice , we have a product returns policy for rhofade which may provide customers a right of return for product purchased within a specified period prior to and subsequent to the product 's expiration date . the right of return lapses upon shipment of the product to a patient . we recorded an estimate for the amount of product which may be returned as a reduction of revenue in the period the related revenue was recognized . our estimates for product returns were based upon available industry data and our own sales information , including visibility into the inventory remaining in the distribution channel . there is no return liability associated with sales of eskata as we had a no returns policy for eskata when we commercialized it . contract research revenue related to laboratory services is generally recognized as the laboratory services are performed , based upon the rates specified in the contracts . under asc topic 606 , we elected to apply the “ right to invoice ” practical expedient when recognizing contract research revenue . we recognize contract research revenue in the amount to which we have the right to invoice . we recognize revenue related to grants as amounts become reimbursable under each grant , which is generally when research is performed , and the related costs are incurred . other revenue licenses of intellectual property – we recognize revenue received from non-refundable , upfront fees related to the licensing of intellectual property when the intellectual property is determined to be distinct from the other performance obligations identified in the arrangement , the license has been transferred to the customer , and the customer is able to use and benefit from the license . milestone payments – at the inception of each arrangement that includes milestone payments , we evaluate whether the milestones are considered probable of being reached and estimate the amount to be included in the transaction price using the most likely amount method . if it is probable that a significant revenue reversal would not occur , the associated milestone value is included in the amount allocated to the license of intellectual property . milestone payments that are not within our control or the control of the customer , such as regulatory approvals , are not considered probable of being achieved until those approvals are received . inventory inventory included the third-party cost of manufacturing and assembly of the finished product forms of eskata and rhofade , quality control and other overhead costs . inventory is stated at the lower of cost or net realizable value . inventory

cash flows the following table summarizes our cash flows for each of the periods presented : replace_table_token_8_th operating activities during the year ended december 31 , 2019 , operating activities used $ 96.4 million of cash primarily resulting from our net loss of $ 161.4 million , partially offset by non-cash adjustments of $ 67.6 million . net cash used by changes in our operating assets and liabilities during the year ended december 31 , 2019 consisted of a $ 5.1 million decrease in accounts payable and accrued expenses and a $ 0.8 million increase in accounts receivable , which were partially offset by a $ 3.7 million decrease in prepaid expenses and other assets . the decrease in accounts payable and accrued expenses was primarily driven by lower levels of expenses , including sales discounts and allowances , as the result of the disposition of rhofade , and lower research and development expenses as a result of the completion of our two pivotal phase 3 clinical trials for a-101 45 % topical solution , as well as the timing of vendor invoicing and payments . the decrease in prepaid expenses and other assets was due to research and development activities primarily related to preclinical development activities for ati-450 and ati-502 , which concluded during the year ended december 31 , 2019 , and the elimination of sales and marketing activities as a result of the disposition of rhofade in october 2019. the increase in accounts receivable was primarily the result of the timing of cash receipts from our contract research customers . non-cash expenses of $ 67.6 million were composed of an intangible asset impairment charge of $ 27.6 million , a goodwill impairment charge of $ 18.5 million , stock-based compensation expense of $ 16.2 million , a charge of $ 0.7 million related to the change in the fair value of contingent consideration and depreciation and amortization expense of $ 6.4 million , partially offset by a gain of $ 1.9 million recognized on the disposition of rhofade .


 Write a concise suspicious activity report of the following text delimited by triple backquotes. Return your response as a formal report which covers the key points highlighting the location,dates,entity names and account holder information in chronological order of the text.
     ```cash flows the following table summarizes our cash flows for each of the periods presented : replace_table_token_8_th operating activities during the year ended december 31 , 2019 , operating activities used $ 96.4 million of cash primarily resulting from our net loss of $ 161.4 million , partially offset by non-cash adjustments of $ 67.6 million . net cash used by changes in our operating assets and liabilities during the year ended december 31 , 2019 consisted of a $ 5.1 million decrease in accounts payable and accrued expenses and a $ 0.8 million increase in accounts receivable , which were partially offset by a $ 3.7 million decrease in prepaid expenses and other assets . the decrease in accounts payable and accrued expenses was primarily driven by lower levels of expenses , including sales discounts and allowances , as the result of the disposition of rhofade , and lower research and development expenses as a result of the completion of our two pivotal phase 3 clinical trials for a-101 45 % topical solution , as well as the timing of vendor invoicing and payments . the decrease in prepaid expenses and other assets was due to research and development activities primarily related to preclinical development activities for ati-450 and ati-502 , which concluded during the year ended december 31 , 2019 , and the elimination of sales and marketing activities as a result of the disposition of rhofade in october 2019. the increase in accounts receivable was primarily the result of the timing of cash receipts from our contract research customers . non-cash expenses of $ 67.6 million were composed of an intangible asset impairment charge of $ 27.6 million , a goodwill impairment charge of $ 18.5 million , stock-based compensation expense of $ 16.2 million , a charge of $ 0.7 million related to the change in the fair value of contingent consideration and depreciation and amortization expense of $ 6.4 million , partially offset by a gain of $ 1.9 million recognized on the disposition of rhofade .
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 Suspicious Activity Report : under this agreement , we may develop these jak inhibitors for the treatment of alopecia areata , or aa , and other dermatological conditions . we paid rigel an upfront nonrefundable payment of $ 8.0 million in 2015 and $ 4.0 million upon the achievement of a specified development milestone in 2019. in addition , we have agreed to make remaining aggregate payments of up to $ 76.0 million upon the achievement of specified development milestones , such as clinical trials and regulatory approvals . further , we have agreed to pay up to an additional $ 10.5 million to rigel upon the achievement of a second set of development milestones . in addition , in connection with the amendment of the agreement in october 2019 , we agreed to pay rigel an amendment fee of $ 1.5 million in three installments of $ 0.5 million in january 2020 , april 2020 and july 2020 , which is included in accrued expenses on our consolidated balance sheet . with respect to any products we commercialize under the rigel license agreement , we will pay rigel quarterly tiered royalties on our annual net sales of each product at a high single digit percentage of annual net sales , subject to specified reductions until the date that all of the patent rights for that product have expired , as determined on a country-by-country and product-by- 61 product basis or , in specified countries under specified circumstances , 10 years from the first commercial sale of such product . the rigel license agreement terminates on the date of expiration of all royalty obligations unless earlier terminated by either party for a material breach . we may also terminate the rigel license agreement without cause at any time upon advance written notice to rigel . rigel , after consultation with us , will be responsible for maintaining and prosecuting the patent rights , and we will have final decision-making authority regarding such patent rights for a product in the united states and the european union . to the extent that we jointly develop intellectual property , we will confer and decide which party will be responsible for filing , prosecuting and maintaining those patent rights . the rigel license agreement also establishes a joint steering committee composed of an equal number of representatives for each party , which will monitor progress in the development of products . stock purchase agreement with vixen pharmaceuticals , inc. and license agreement with columbia university in march 2016 , we entered into a stock purchase agreement , or the vixen agreement , with vixen pharmaceuticals , inc. , or vixen , and jak1 , llc , jak2 , llc and jak3 , llc , or together , the selling stockholders , and shareholder representative services llc as the representative of the selling stockholders . pursuant to the vixen agreement , we acquired all shares of vixen 's capital stock from the selling stockholders , or the vixen acquisition . following the vixen acquisition , vixen became our wholly-owned subsidiary . pursuant to the vixen agreement , we paid $ 0.6 million upfront and issued an aggregate of 159,420 shares of our common stock to the selling stockholders . we are obligated to make annual payments of $ 0.1 million through march 2022 , with such amounts being creditable against specified future payments that may be paid under the vixen agreement . under the vixen agreement we are obligated to make aggregate payments of up to $ 18.0 million to the selling stockholders upon the achievement of specified pre-commercialization milestones for three products covered by the vixen patent rights in the united states , the european union and japan , and aggregate payments of up to $ 22.5 million upon the achievement of specified commercial milestones for products covered by the vixen patent rights . with respect to any covered products that we commercialize under the vixen agreement , we are obligated to pay low single-digit royalties on net sales , subject to specified reductions , limitations and other adjustments , until the date that all of the patent rights for that product have expired , as determined on a country-by-country and product-by-product basis or , in specified circumstances , ten years from the first commercial sale of such product . if we sublicense any of vixen 's patent rights and know-how acquired pursuant to the vixen agreement , we will be obligated to pay a portion of any consideration we receive from such sublicenses in specified circumstances . as a result of the vixen acquisition , we became party to the exclusive license agreement , by and between vixen and the trustees of columbia university in the city of new york , or columbia , dated as of december 31 , 2015 , or , as amended , the columbia license agreement . under the columbia license agreement , we are obligated to pay columbia an annual license fee of $ 10,000 subject to specified adjustments for patent expenses incurred by columbia and creditable against any royalties that may be paid under the columbia license agreement . we are also obligated to pay up to an aggregate of $ 11.6 million upon the achievement of specified commercial milestones , including specified levels of net sales of products covered by columbia patent rights and or know-how , and royalties at a sub-single-digit percentage of annual net sales of products covered by columbia patent rights and or know-how , subject to specified adjustments . if we sublicense any of columbia 's patent rights and know-how acquired pursuant to the columbia license agreement , we will be obligated to pay columbia a portion of any consideration received from such sublicenses in specified circumstances . story_separator_special_tag we recognize revenue when collection of the consideration we are entitled to under a contract with a customer is probable . at contract inception , we assess the goods or services promised within a contract with a customer to identify the performance obligations , and to determine if they are distinct . we recognize revenue that is allocated to each distinct performance obligation when ( or as ) that performance obligation is satisfied . we only recognize revenue when collection of the consideration we are entitled to under a contract with a customer is probable . product sales , net we recognized revenue from product sales at the point the customer obtained control , which generally occurred upon delivery . we also included estimates of variable consideration in the same period revenue was recognized . components of variable consideration included trade discounts and allowances , product returns , government rebates , discounts and rebates , other incentives such as patient co-pay assistance , and other fee for service amounts . variable consideration was recorded on the consolidated balance sheet as either a reduction of accounts receivable , if payable to a customer , or as a current liability , if payable to a third-party other than a customer . we considered all relevant information when estimating variable consideration such as contractual and statutory requirements , specific known market events and trends , industry data and forecasted customer buying and payment patterns . the amount of net revenue that can be recognized is constrained by estimates of variable consideration which are included in the transaction price . payment terms with customers did not exceed one year and , therefore , we did not account for a financing component in our arrangements . we expensed incremental costs of obtaining a contract with a customer , including sales commissions , when incurred as the period of benefit was less than one year . trade discounts and allowances - we provided customers with trade discounts , rebates , allowances and or other incentives . we recorded estimates for these items as a reduction of revenue in the same period the revenue was recognized . government and payor rebates – we contracted with , or were subject to arrangements with , certain third-party payors , including pharmacy benefit managers and government agencies , for the payment of rebates with respect to utilization of our commercial products . we also entered into agreements with gpos that provided for administrative fees and discounted pricing in the form of volume-based rebates . we were also subject to discount and rebate obligations under state medicaid programs and medicare . we recorded estimates for these discounts and rebates as a reduction of revenue in the same period the revenue was recognized . 67 other incentives – we maintained a co-pay assistance program which was intended to provide financial assistance to qualified commercially-insured patients with prescription drug co-payments required by third-party payors . we estimated and recorded accruals for these incentives as a reduction of revenue in the period the revenue was recognized . our estimated amounts for co-pay assistance were based upon the number of claims and the cost per claim that we expected to receive associated with product that had been sold to customers but remained in the distribution channel at the end of each reporting period . product returns - consistent with industry practice , we have a product returns policy for rhofade which may provide customers a right of return for product purchased within a specified period prior to and subsequent to the product 's expiration date . the right of return lapses upon shipment of the product to a patient . we recorded an estimate for the amount of product which may be returned as a reduction of revenue in the period the related revenue was recognized . our estimates for product returns were based upon available industry data and our own sales information , including visibility into the inventory remaining in the distribution channel . there is no return liability associated with sales of eskata as we had a no returns policy for eskata when we commercialized it . contract research revenue related to laboratory services is generally recognized as the laboratory services are performed , based upon the rates specified in the contracts . under asc topic 606 , we elected to apply the “ right to invoice ” practical expedient when recognizing contract research revenue . we recognize contract research revenue in the amount to which we have the right to invoice . we recognize revenue related to grants as amounts become reimbursable under each grant , which is generally when research is performed , and the related costs are incurred . other revenue licenses of intellectual property – we recognize revenue received from non-refundable , upfront fees related to the licensing of intellectual property when the intellectual property is determined to be distinct from the other performance obligations identified in the arrangement , the license has been transferred to the customer , and the customer is able to use and benefit from the license . milestone payments – at the inception of each arrangement that includes milestone payments , we evaluate whether the milestones are considered probable of being reached and estimate the amount to be included in the transaction price using the most likely amount method . if it is probable that a significant revenue reversal would not occur , the associated milestone value is included in the amount allocated to the license of intellectual property . milestone payments that are not within our control or the control of the customer , such as regulatory approvals , are not considered probable of being achieved until those approvals are received . inventory inventory included the third-party cost of manufacturing and assembly of the finished product forms of eskata and rhofade , quality control and other overhead costs . inventory is stated at the lower of cost or net realizable value . inventory

