sub holder

Companies have 2 days to lodge the substantial holder form 603.

You'll see from the announcement that Vanguard became a sub holder on Monday (17th) and at this point they had interest in 42.29m shares.

The market has turned over another 93.3 million CNP shares since Monday.

The have either bought a whole lot more since, or someone else is buying. Expect to see a change in sub holder notice OR another sub holder appearing in the next few days.