In fact, it's a little more complicated than that. I guess the WSJ guy is right that GAAP gives that harebrained guidance about control being lost for collateral in excess of 102% of loan value, but it's likely that's not what Lehman was doing. According to the FT alphaville piece What's in Repo 105 that I linked to here

Lehman's own accounting policy required assets used for Repo 105 "be readily obtainable" -- i.e. liquid -- according to the report. Lehman's lawyers also recommended they be liquid so that "the Buyer could easily dispose of the Purchased Securities and acquire equivalent securities if it wished."

The first time I read that it struck me as odd - in a regular repo, the parties commit to exchanging the exact same security at the beginning and end of the transaction. But Lehman's, in order to make sure that the loss of control GAAP guidance applied, must have written into its repo contracts a clause allowing the counterparty to dispose of the collateral at will, as long as it returned an equivalent security at the end of the repo's life. But in order for this to be a meaningful clause, the security must have been highly liquid. Hence the internal requirement by the lawyers (not the accountants) that the assets be highly liquid.

Clever little buggers, Lehman Brothers...

The brainless should not be in banking -- Willem Buiter