"They just took my code and filed off the copyright" said Søren. "This is clearest with the two header files hptraid.h and pdcraid.h. Compare these with FreeBSD's ata-raid.h, and just look at the similarities." And it's true that these two header files certainly look like a chopped up copy of the FreeBSD header, after a quick search-and-replace. "The reading of the RAID config from the disks is their own code, but is clearly "inspired" from our code," said Søren, "but that's encouraged by the license. It's the verbatim use of the other code without retaining the copyright that's the problem."
ata-raid.h, and the other files, are copyright Søren, and released under the three clause BSD license, which includes the restriction "Redistributions of source code must retain the above copyright notice". So using these files, or significant portions of them, in your own code, without retaining the copyright information, as has happened here, is prohibited.
You may be thinking "This is only a couple of header files, what's the big deal?". As Søren says "The problem here is that the structures in the headers is the whole story. That info tells how you read the proprietary struct off the disks, and was reverse engineered and documented by me after a lot of effort." Søren's intellectual property is tied up in those files.
Right now, Søren is in discussions with the authors of the Linux ATA drivers (employed by RedHat) to ensure that his copyright notice is returned to these and other files, and to ensure that this situation does not recur. And it is hoped that an amicable solution can be reached.