Can collection agency add negative items to credit report after orig debt's SOL has expired?

Sorry, this is my 3rd and final (hopefully) question about credit reports :) I'm in California, and it appears that the state's Statute of Limitations for credit card debt collection is 4 years from the date of the last payment. So if I had a debt that wasn't fully paid in 2001, it's on my... show more Sorry, this is my 3rd and final (hopefully) question about credit reports :)

I'm in California, and it appears that the state's Statute of Limitations for credit card debt collection is 4 years from the date of the last payment.

So if I had a debt that wasn't fully paid in 2001, it's on my credit report from the original creditor. This is fine, as I know it can stay for 7 years. But, since the SoL has expired (In July 2005, which was 4 years after the last payment), they have sold it off to a collection agency.

While I also realize that the collections agency can still contact me to "convince" me to pay it, I don't believe legally they can do anything about it now other than harass me. (Hopefully this is correct so far?)

But, can that collections agency legally keep adding new negative items to my credit report? It would seem to me that since the debt is past the SoL and expired, that while they can harass me, they can't actually add items to my credit report about it. Any ideas?
Update: Just something to add: I realize that they can keep reporting it until the debt is expired. But some of you have stated that the SoL has nothing to do with the debt collectors adding negative items to your credit report, but then say that they may do so when the account is "within the reporting... show more Just something to add:
I realize that they can keep reporting it until the debt is expired. But some of you have stated that the SoL has nothing to do with the debt collectors adding negative items to your credit report, but then say that they may do so when the account is "within the reporting period"...so does this mean that they can report it until the 7 year mark of the date that the original debt is removed, and then they must stop?

Or again, does this mean that they are bound to some other "reporting period". I'm confused now...
10 answers 10