vimseltinib we are currently studying vimseltinib in an open-label phase 1/2 study designed to evaluate the safety , efficacy , pk , and pd of vimseltinib in patients with malignant solid tumors as well as patients with tgct . in november 2020 , we announced the selection of a phase 2 dose and initiated the expansion portion of the study with vimseltinib in patients with symptomatic tgct not suitable for surgery . we are continuing to enroll tgct patients in cohort 9 of the dose escalation portion of the study to complete enrollment in this cohort . we expect to present updated data for vimseltinib in the second half of 2021. rebastinib we are currently studying rebastinib in two phase 1b/2 studies in combination with chemotherapy , one with paclitaxel and one with carboplatin . in october 2018 , we initiated an open-label , multicenter , phase 1b/2 study of rebastinib in combination with paclitaxel to assess safety , tolerability , pk , and efficacy in patients with advanced or metastatic solid tumors . in january 2019 , we initiated an open-label , multicenter , phase 1b/2 study of rebastinib in combination with carboplatin in patients with advanced or metastatic solid tumors . in january 2020 , we selected a phase 2 dose for , and activated , part 2 of the phase 1b/2 study of rebastinib in combination with carboplatin . in may 2020 , we announced that in part 2 of the study of rebastinib in combination with paclitaxel , we observed the required number of responses in the first stage in both the endometrial and platinum-resistant ovarian cancer cohorts , triggering the expansion of enrollment in these cohorts . in addition , based on the clinical activity observed in part 1 , we added a cohort for patients with carcinosarcoma in part 2 of the study of rebastinib in combination with paclitaxel . we expect to present updated data from the study of rebastinib in combination with paclitaxel in patients with endometrial cancer in the second quarter of 2021 and in patients with proc in the second half of 2021. dcc-3116 in january 2021 , we announced our plans to initiate a phase 1 study of dcc-3116 in the second quarter of 2021 , subject to fda authorization to proceed under our ind for dcc-3116 , submitted in the fourth quarter of 2020 and cleared by the fda . coronavirus ( covid-19 ) the full extent to which the covid-19 pandemic , or the future outbreak of any other highly infectious or contagious diseases , may impact our business , including our preclinical studies , clinical trial operations , or commercialization efforts will depend on continuously changing circumstances , which are highly uncertain and can not be predicted at this time , such as the duration of such pandemic including future waves of infection , new strains of the virus that causes covid-19 , or the broad availability of effective vaccines , the actions taken to contain the pandemic or mitigate its impact , and the direct and indirect economic effects of the pandemic and containment measures , among others . the ongoing fluidity of this situation precludes any prediction as to the full impact of the covid-19 pandemic but it could have a material adverse effect on our business , financial condition , and results of operations . the covid-19 pandemic may also have the effect of heightening the risks to which we are subject , including various aspects of our preclinical studies and ongoing clinical trials , the reliance on third parties in our supply chain for materials and manufacturing of our drug and drug candidates , disruptions in health regulatory agencies ' operations globally , the volatility of our common stock , our ability to access capital markets , and our ability to successfully launch , commercialize , and generate revenue from qinlock . we are continuing to assess the long-term impact of covid-19 on our business operations in an effort to mitigate interruption to our clinical programs , research efforts , commercial launch of qinlock , and other business activities and to ensure the safety and well-being of our employees , as well as the physicians and patients participating in our clinical studies . because covid-19 infections have been reported throughout the u.s. and worldwide , certain national , state , and local governmental authorities have issued orders , proclamations , and or directives aimed at minimizing the spread of covid-19 . although some of these restrictions were eased or lifted , in response to local surges and new waves of infection , some countries , states , and local governments have reinstituted these restrictions , and additional , more restrictive orders , proclamations , and or directives may be issued in the future . in response to the covid-19 pandemic , we have implemented precautionary measures to protect the health and safety of our employees , partners , and patients , including encouraging all employees , other than those engaged in laboratory research activities , to work-from-home , and requiring adherence to onsite occupancy limits and appropriate safety measures designed to comply with federal , state , and local guidelines . 105 our ability to successfully launch , commercialize , and generate revenue from qinlock may be adversely affected by the impact of the covid-19 pandemic . for example , limited hospital access for non-patients , social distancing requirements , and precautionary measures due to covid-19 have impacted the ability of our sales personnel to interact in-person with customers . in response , we have implemented a virtual launch model , which may adversely affect the ability of our sales professionals to effectively market qinlock to physicians , which may have a negative impact on our sales and our market penetration . in addition , in the u.s. we are utilizing various programs to help patients afford our products , including patient assistance programs for eligible patients . story_separator_special_tag chargebacks and administrative fees : chargebacks for discounts represent our estimated obligations resulting from contractual commitments to sell product to qualified healthcare providers and government agencies at prices lower than the list 109 prices charged to the customers who directly purchase the product from us . the customers charge us for the difference between what the customers pay us for the product and the customer 's ultimate contractually committed or government required lower selling price to the qualified healthcare providers . as part of our contractual commitments to sell product to qualified healthcare providers , we pay fees for administrative services , such as account management and data reporting . government rebates : government rebates consist of medicare , tricare , and medicaid rebates . these reserves are recorded in the same period the related revenue is recognized . for medicare , we also estimate the number of patients in the prescription drug coverage gap for whom we will owe a rebate under the medicare part d program . trade discounts and allowances : we provide customers with discounts that are explicitly stated in contracts and recorded in the period the related product revenue is recognized . in addition , we also receive sales order management , inventory management , and data services from customers in exchange for certain fees . product returns : we estimate the amount of our product sales that may be returned by our customers and record this estimate in the period the related product revenue is recognized . we currently estimate product return liabilities based on available industry data and our visibility into the inventory remaining in the distribution channel . other incentives : other incentives include co-payment assistance provided to qualified patients , whereby we may provide financial assistance to patients with prescription drug co-payments required by the patient 's insurance provider . reserves for co-payment assistance are recorded in the same period the related revenue is recognized . accrued research and development expenses as part of the process of preparing our consolidated financial statements , we are required to estimate our accrued research and development expenses . this process involves reviewing open contracts and purchase orders , communicating with our applicable personnel to identify services that have been performed on our behalf , and estimating the associated cost incurred for the services when we have not yet been invoiced or otherwise notified of actual costs . the majority of our service providers invoice us in arrears for services performed , on a pre-determined schedule or when contractual milestones are met ; however , some require advance payments . we make estimates of our accrued expenses as of each balance sheet date in the consolidated financial statements based on facts and circumstances known to us at that time . we periodically confirm the accuracy of the estimates with the service providers and make adjustments if necessary . examples of estimated accrued research and development expenses include fees paid to : vendors in connection with the preclinical development activities ; cmos in connection with the production of preclinical and clinical trial materials ; cros in connection with preclinical and clinical studies ; and investigative sites in connection with clinical trials . we base our expenses related to preclinical studies and clinical trials on our estimates of the services received and efforts expended pursuant to quotes and contracts with multiple research institutions and cros that conduct and manage preclinical studies and clinical trials on our behalf . the financial terms of these agreements are subject to negotiation , vary from contract to contract and may result in uneven payment flows . there may be instances in which payments made to our vendors will exceed the level of services provided and result in a prepayment of the expense . in accruing service fees , we estimate the time period over which services will be performed and the level of effort to be expended in each period . if the actual timing of the performance of services or the level of effort varies from the estimate , we adjust the accrual or prepaid expense accordingly . although we do not expect our estimates to be materially different from amounts actually incurred , our understanding of the status and timing of services performed relative to the actual status and timing of services performed may vary and may result in reporting amounts that are too high or too low in any particular period . to date , there have not been any material adjustments to our prior estimates of accrued research and development expenses . stock-based compensation we measure all stock option awards granted to employees and directors based on the fair value on the date of the grant and recognize compensation expense of those awards over the requisite service period , which is generally the vesting period of the respective award . the straight-line method of expense recognition is applied to all awards with service-only conditions . we estimate the fair value of each stock option award using the black-scholes option-pricing model , which uses as inputs the fair value of our common stock and assumptions we make for the volatility of our common stock , the expected term of our 110 stock-based awards , the risk-free interest rate for a period that approximates the expected term of our stock-based awards , and our expected dividend yield . prior to october 2017 , we were a privately-held company and lacked company-specific historical and implied volatility information . therefore , we estimate our expected volatility based on the historical volatility of a set of our publicly traded peer companies as well as the limited historical volatility of our own traded stock price . we estimate the expected term of our options using the `` simplified `` method for awards that qualify as `` plain-vanilla `` options . the risk-free interest rate is determined by reference to the u.s. treasury yield curve in effect at the time of grant of the

cash flows as of december 31 , 2020 , our principal sources of liquidity were cash , cash equivalents , and marketable securities of $ 561.3 million , which consisted of cash , money market funds , u.s. government securities , commercial paper , corporate debt securities , and certificates of deposit . the primary objectives of our investment activities are to preserve principal , provide liquidity , and maximize income without significantly increasing risk . given the nature of these investments , we believe that the market for these instruments is not illiquid . the following table summarizes our sources and uses of cash and cash equivalents for each of the periods presented : replace_table_token_6_th operating activities during the year ended december 31 , 2020 compared to the same period in 2019 , net cash used by operating activities increased $ 90.4 million , primarily resulting from an increase in our net loss of $ 74.2 million and increases in net cash outflows related to changes in our operating assets and liabilities of $ 38.6 million , partially offset by increases in net non-cash charges of $ 22.5 million . the increase in net cash outflows related to changes in our operating assets and liabilities was primarily due to an increase in accounts receivable of $ 13.9 million and an increase in inventory of $ 3.2 million . the increases in accounts receivable and inventory were primarily associated with sales of qinlock and the commencement of the capitalization of qinlock inventory , respectively , following the fda approval of qinlock in may 2020. other net cash outflows related to changes in our operating assets and liabilities were generally due to the timing of vendor invoicing and payments . net non-cash charges increased primarily due to an increase in share-based compensation of $ 16.7 million .


 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 as of december 31 , 2020 , our principal sources of liquidity were cash , cash equivalents , and marketable securities of $ 561.3 million , which consisted of cash , money market funds , u.s. government securities , commercial paper , corporate debt securities , and certificates of deposit . the primary objectives of our investment activities are to preserve principal , provide liquidity , and maximize income without significantly increasing risk . given the nature of these investments , we believe that the market for these instruments is not illiquid . the following table summarizes our sources and uses of cash and cash equivalents for each of the periods presented : replace_table_token_6_th operating activities during the year ended december 31 , 2020 compared to the same period in 2019 , net cash used by operating activities increased $ 90.4 million , primarily resulting from an increase in our net loss of $ 74.2 million and increases in net cash outflows related to changes in our operating assets and liabilities of $ 38.6 million , partially offset by increases in net non-cash charges of $ 22.5 million . the increase in net cash outflows related to changes in our operating assets and liabilities was primarily due to an increase in accounts receivable of $ 13.9 million and an increase in inventory of $ 3.2 million . the increases in accounts receivable and inventory were primarily associated with sales of qinlock and the commencement of the capitalization of qinlock inventory , respectively , following the fda approval of qinlock in may 2020. other net cash outflows related to changes in our operating assets and liabilities were generally due to the timing of vendor invoicing and payments . net non-cash charges increased primarily due to an increase in share-based compensation of $ 16.7 million .
```    
 Suspicious Activity Report : vimseltinib we are currently studying vimseltinib in an open-label phase 1/2 study designed to evaluate the safety , efficacy , pk , and pd of vimseltinib in patients with malignant solid tumors as well as patients with tgct . in november 2020 , we announced the selection of a phase 2 dose and initiated the expansion portion of the study with vimseltinib in patients with symptomatic tgct not suitable for surgery . we are continuing to enroll tgct patients in cohort 9 of the dose escalation portion of the study to complete enrollment in this cohort . we expect to present updated data for vimseltinib in the second half of 2021. rebastinib we are currently studying rebastinib in two phase 1b/2 studies in combination with chemotherapy , one with paclitaxel and one with carboplatin . in october 2018 , we initiated an open-label , multicenter , phase 1b/2 study of rebastinib in combination with paclitaxel to assess safety , tolerability , pk , and efficacy in patients with advanced or metastatic solid tumors . in january 2019 , we initiated an open-label , multicenter , phase 1b/2 study of rebastinib in combination with carboplatin in patients with advanced or metastatic solid tumors . in january 2020 , we selected a phase 2 dose for , and activated , part 2 of the phase 1b/2 study of rebastinib in combination with carboplatin . in may 2020 , we announced that in part 2 of the study of rebastinib in combination with paclitaxel , we observed the required number of responses in the first stage in both the endometrial and platinum-resistant ovarian cancer cohorts , triggering the expansion of enrollment in these cohorts . in addition , based on the clinical activity observed in part 1 , we added a cohort for patients with carcinosarcoma in part 2 of the study of rebastinib in combination with paclitaxel . we expect to present updated data from the study of rebastinib in combination with paclitaxel in patients with endometrial cancer in the second quarter of 2021 and in patients with proc in the second half of 2021. dcc-3116 in january 2021 , we announced our plans to initiate a phase 1 study of dcc-3116 in the second quarter of 2021 , subject to fda authorization to proceed under our ind for dcc-3116 , submitted in the fourth quarter of 2020 and cleared by the fda . coronavirus ( covid-19 ) the full extent to which the covid-19 pandemic , or the future outbreak of any other highly infectious or contagious diseases , may impact our business , including our preclinical studies , clinical trial operations , or commercialization efforts will depend on continuously changing circumstances , which are highly uncertain and can not be predicted at this time , such as the duration of such pandemic including future waves of infection , new strains of the virus that causes covid-19 , or the broad availability of effective vaccines , the actions taken to contain the pandemic or mitigate its impact , and the direct and indirect economic effects of the pandemic and containment measures , among others . the ongoing fluidity of this situation precludes any prediction as to the full impact of the covid-19 pandemic but it could have a material adverse effect on our business , financial condition , and results of operations . the covid-19 pandemic may also have the effect of heightening the risks to which we are subject , including various aspects of our preclinical studies and ongoing clinical trials , the reliance on third parties in our supply chain for materials and manufacturing of our drug and drug candidates , disruptions in health regulatory agencies ' operations globally , the volatility of our common stock , our ability to access capital markets , and our ability to successfully launch , commercialize , and generate revenue from qinlock . we are continuing to assess the long-term impact of covid-19 on our business operations in an effort to mitigate interruption to our clinical programs , research efforts , commercial launch of qinlock , and other business activities and to ensure the safety and well-being of our employees , as well as the physicians and patients participating in our clinical studies . because covid-19 infections have been reported throughout the u.s. and worldwide , certain national , state , and local governmental authorities have issued orders , proclamations , and or directives aimed at minimizing the spread of covid-19 . although some of these restrictions were eased or lifted , in response to local surges and new waves of infection , some countries , states , and local governments have reinstituted these restrictions , and additional , more restrictive orders , proclamations , and or directives may be issued in the future . in response to the covid-19 pandemic , we have implemented precautionary measures to protect the health and safety of our employees , partners , and patients , including encouraging all employees , other than those engaged in laboratory research activities , to work-from-home , and requiring adherence to onsite occupancy limits and appropriate safety measures designed to comply with federal , state , and local guidelines . 105 our ability to successfully launch , commercialize , and generate revenue from qinlock may be adversely affected by the impact of the covid-19 pandemic . for example , limited hospital access for non-patients , social distancing requirements , and precautionary measures due to covid-19 have impacted the ability of our sales personnel to interact in-person with customers . in response , we have implemented a virtual launch model , which may adversely affect the ability of our sales professionals to effectively market qinlock to physicians , which may have a negative impact on our sales and our market penetration . in addition , in the u.s. we are utilizing various programs to help patients afford our products , including patient assistance programs for eligible patients . story_separator_special_tag chargebacks and administrative fees : chargebacks for discounts represent our estimated obligations resulting from contractual commitments to sell product to qualified healthcare providers and government agencies at prices lower than the list 109 prices charged to the customers who directly purchase the product from us . the customers charge us for the difference between what the customers pay us for the product and the customer 's ultimate contractually committed or government required lower selling price to the qualified healthcare providers . as part of our contractual commitments to sell product to qualified healthcare providers , we pay fees for administrative services , such as account management and data reporting . government rebates : government rebates consist of medicare , tricare , and medicaid rebates . these reserves are recorded in the same period the related revenue is recognized . for medicare , we also estimate the number of patients in the prescription drug coverage gap for whom we will owe a rebate under the medicare part d program . trade discounts and allowances : we provide customers with discounts that are explicitly stated in contracts and recorded in the period the related product revenue is recognized . in addition , we also receive sales order management , inventory management , and data services from customers in exchange for certain fees . product returns : we estimate the amount of our product sales that may be returned by our customers and record this estimate in the period the related product revenue is recognized . we currently estimate product return liabilities based on available industry data and our visibility into the inventory remaining in the distribution channel . other incentives : other incentives include co-payment assistance provided to qualified patients , whereby we may provide financial assistance to patients with prescription drug co-payments required by the patient 's insurance provider . reserves for co-payment assistance are recorded in the same period the related revenue is recognized . accrued research and development expenses as part of the process of preparing our consolidated financial statements , we are required to estimate our accrued research and development expenses . this process involves reviewing open contracts and purchase orders , communicating with our applicable personnel to identify services that have been performed on our behalf , and estimating the associated cost incurred for the services when we have not yet been invoiced or otherwise notified of actual costs . the majority of our service providers invoice us in arrears for services performed , on a pre-determined schedule or when contractual milestones are met ; however , some require advance payments . we make estimates of our accrued expenses as of each balance sheet date in the consolidated financial statements based on facts and circumstances known to us at that time . we periodically confirm the accuracy of the estimates with the service providers and make adjustments if necessary . examples of estimated accrued research and development expenses include fees paid to : vendors in connection with the preclinical development activities ; cmos in connection with the production of preclinical and clinical trial materials ; cros in connection with preclinical and clinical studies ; and investigative sites in connection with clinical trials . we base our expenses related to preclinical studies and clinical trials on our estimates of the services received and efforts expended pursuant to quotes and contracts with multiple research institutions and cros that conduct and manage preclinical studies and clinical trials on our behalf . the financial terms of these agreements are subject to negotiation , vary from contract to contract and may result in uneven payment flows . there may be instances in which payments made to our vendors will exceed the level of services provided and result in a prepayment of the expense . in accruing service fees , we estimate the time period over which services will be performed and the level of effort to be expended in each period . if the actual timing of the performance of services or the level of effort varies from the estimate , we adjust the accrual or prepaid expense accordingly . although we do not expect our estimates to be materially different from amounts actually incurred , our understanding of the status and timing of services performed relative to the actual status and timing of services performed may vary and may result in reporting amounts that are too high or too low in any particular period . to date , there have not been any material adjustments to our prior estimates of accrued research and development expenses . stock-based compensation we measure all stock option awards granted to employees and directors based on the fair value on the date of the grant and recognize compensation expense of those awards over the requisite service period , which is generally the vesting period of the respective award . the straight-line method of expense recognition is applied to all awards with service-only conditions . we estimate the fair value of each stock option award using the black-scholes option-pricing model , which uses as inputs the fair value of our common stock and assumptions we make for the volatility of our common stock , the expected term of our 110 stock-based awards , the risk-free interest rate for a period that approximates the expected term of our stock-based awards , and our expected dividend yield . prior to october 2017 , we were a privately-held company and lacked company-specific historical and implied volatility information . therefore , we estimate our expected volatility based on the historical volatility of a set of our publicly traded peer companies as well as the limited historical volatility of our own traded stock price . we estimate the expected term of our options using the `` simplified `` method for awards that qualify as `` plain-vanilla `` options . the risk-free interest rate is determined by reference to the u.s. treasury yield curve in effect at the time of grant of the

