Update from 2:50 p.m. EDTHomebuilders Centex ( CTX), Lennar ( LEN) and Pulte Homes ( PHM) were rising Thursday despite a downgrade from Moody's that affects $9.4 billion of their debt securities and $3.25 billion of commercial paper authorizations. Centex, Lennar and Pulte were each assigned corporate family ratings of Ba1. All three were also given negative ratings outlooks and were taken off review for downgrade, where they had been placed on Aug. 22. Moody's lowered its rating on senior unsecured notes issued by Centex and Lennar to Ba1 from Baa2 and cut each of their commercial paper ratings to not prime from prime-2. Pulte's senior unsecured rating was dropped to Ba1 from Baa3 previously. The downgrade came about because Moody's said it doesn't see a housing sector recovery beginning before 2009 at the earliest, "with any recovery likely to be very measured at first, thus prolonging the companies' underperformance on key financial metrics vs. prior expectations." Still, shares of all three rose. Centex was gaining 2.1% to $29.95, and Lennar was up 1.5% to $25.69. Pulte was higher by 2.1% at $15.68. Elsewhere, in the group, Beazer Homes ( BZH) said its profit from past years will be restated upward following an audit committee investigation. The company said the probe revealed that its reserves for land and home costs were too high in previous years. Shares of Beazer were up 3.4% at $10.27.