Originally Posted by oldskewel

As far as I know, for my 2001 3.0i, the original regulators were made by Brose. They have BMW roundels and Brose stamped on them.

You might want to look at a recent thread here on OE vs. OEM vs. Genuine vs. OES vs. aftermarket vs. etc. It is fairly complicated, especially when everybody seems to have different understandings of what the labels mean.

So if your new parts say BMW, they are definitely Genuine parts (well, unless they are straight-up fake, which is not yet common here). If they don't say BMW, but say Brose, they would be considered OES (since Brose originally supplied [the "S" in OES] this exact part to originally built cars), or OE (since the S is sometimes not included, and OE means the same as OES). And sometimes, I have seen Genuine parts (for BMW and other brands) that don't have the BMW logo, just the OES or OE brand, so if you have that, I would not worry. Either way, you are good to go with Brose.