Blackrock’s massive Friday afternoon dump…

As we monitored filings on Friday afternoon, we wondered why EDGAR seemed unusually sluggish. But it wasn’t until late Friday that we realized why: Blackrock (BLK) had done a massive document dump on Friday afternoon of 13G filings related to its acquisition of Barclay’s Global Investors.

We counted over 1,800 13Gs that Blackrock dumped on Friday, which explains why EDGAR might have been a tad bit pokey. The stream started at just after 2 p.m. est and didn’t let up until just after 4:30, when the last one, which reported a 6.5% stake in Vodafone came in. For those less familiar with the 13G, since we don’t often write about these filings, it’s a requirement when ownership exceeds 5% of the outstanding shares. With few rare exceptions, these filings represented new positions for Blackrock since we only counted 11 amended 13Gs, which in itself seems very surprising, given the long list of stocks.

Though it’s hard to tell from the SEC’s EDGAR database the names of those 1,800-plus companies without clicking on each filing (and who has time to click on 1,800 of them?), it’s a bit easier in 10KWizard (now known as Morningstar Document Research). And, indeed, there’s a lot of household names on the list including some big names in tech like Apple (AAPL), AOL (AOL), Google (GOOG), Yahoo (YHOO) — several of which Dow Jones picked up on on Friday afternoon. But there’s a lot more names on the list too, including United Technologies (UTX), Toll Brothers (TOL), and even footnoted frequent flyer Martha Stewart Omnimedia (MSO) where Blackrock disclosed a stake of just over 7%.

Actually, a far more interesting project might be trying to figure out who wasn’t on the list since with 1,800-plus filings, just about any company over even a relatively modest market cap — Martha Stewart’s is currently around $240 million — seems to have made the cut.