The trouble is that the US Supreme Court has said that you can not copyright a database unless you have done some form of creative work on the data, such as algorithm. Mere effort in compiling doesn't do it. On this basis Celera risked handing over all its precious data if it followed the conventional system. Kennedy felt he was faced with Hobson's choice. He could either find a way of making it possible for Celera to publish, or risk these data being locked away.
Companies have always read scientific journals and kept their own research confidential.
What's new now is that while retaining control over their data they are seeking to gain academic legitimacy by publishing their work in peer-review journals. In this case, the move can be seen as a way of academic publishing increasing its scope of activity so that it is more accessible to commercial ventures. One intriguing aspect of this issue is that in private conversations, many leading scientists express anxieties that this is setting a dangerous precedent, but ask people to go on record and a deathly hush descends. Former director of the NIH Harold Varmus raised the temperature when he took a leading role in writing a letter expressing concern about the issue, but has since then consistently refused to comment on the issue. Others just say that they are too busy to comment.