What's your Point ? Yes, we all know Deposits are 'liabilities' but JPMC 'took the CASH$$ Deposits" of WMB, so it did not "just agree to take on a $300B Liability 'Out of Thin Air' when it Bid to FDIC for WaMu, so it 'got the CASH$$ Accounts of $300BB from WMB' and hence they 'took on a liability' because they are the "Customer's CASH$$ Deposits' that got 'transferred' to JPMC...
Now, at the same time, they 'assumed/Took All the 'Assets' of WaMu too , OR Rather They signed the PAA with FDIC to "Buy those Assets'...We don't know IF JPMC picked up ALL the servicing Rights for WaMu's MBS Assets but looks like they got a Major portion of those and have been making money off Servicing those Mortgages while some may have gone to COOP also...
Regardless, it is very clear that JPMC has not Paid for those Assets that are still under FDIC-R Conservatorship...