I saw it first from Lance Zierlein:
Then Drew Dougherty elaborated:
With #Texans OL Brennan Williams on PUP, he's limited to non-contact work w/club trainer or physician, and can attend meetings.— Drew Dougherty (@DoughertyDrew) July 23, 2013
Williams can take part in contact drills during camp if he's pulled off PUP.— Drew Dougherty (@DoughertyDrew) July 23, 2013
As Tania Ganguli notes, Williams being placed on the PUP list at the outset of training camp does not necessarily mean he'll start the season on the PUP list:
Corrected that first tweet, sorry. #Texans announced Williams to PUP now. The training camp version does not mean he'll start season there.— Tania Ganguli (@taniaganguli) July 23, 2013
So #Texans can take Williams off PUP if he gets healthy during camp. Whether he needs to be on it to start season can be determined later.— Tania Ganguli (@taniaganguli) July 23, 2013
Circling back to LZ's point, this does likely mean that any hopes Texans fans had about Brennan Williams starting at right tackle come Week One of the regular season are all but dashed. With Derek Newton coming off a surgery of his own, it looks like Ryan Harris and/or David Quessenberry will be getting the lion's share of the work at RT throughout camp.