This assay is commonly performed in our laboratory as part of the diagnostic workup for bleeding disorders, but suffers from four major limitations: (i) it is time-consuming, (ii) samples have to be drawn and processed on melting ice [9, 10], (iii) there is no harmonized and standardized procedure between laboratories, (iv) and as it is performed with a plasma sample artificially depleted in fibrinolysis inhibitors (mostly alpha-2-antiplasmin with less than 10% left, and PAI-1 and TAFI with respectively 42% and 38% left [11]); it does not reflect the whole in vivo phenomenon. Here, SERPINE1 is linked to hemorrhagic disease.