The new official rule for sigs

With Signature Images:
-Cannot be over 50kb in file size
-Cannot be over 500px Wide
-Cannot be over 200px Tall
-No more than 2 lines of text under the image

Without Signature Images:
-No more than 4 lines of text
-No external links to competing sites or sites for profit
-Links to personal sites that don't violate the TOS or the rule above are fine.

Also, as stated here
NO commercial advertising anywhere:
No links to commercial sites in your profiles,
sigs or avatars.

No Campaign Programs for unrecognized organizations.

No company logos in sigs or avatars. (Windows, Apple , Linux are ok)

No links to your own "for profit" website
If you make money on anything on your site,do not link on Pronet.

No solicitation for donations

No link to a competitive website
If you have a similar forum as Pronet,no link allowed.

NO links to adult content(will result in a ban)

NO reference to politics,religion, sex, contraband, or alcohol.

No links to foreign language websites, of any kind.

This section of our TOS is regularly investigated, and noncompliance will result in removal of infraction from your profile, with no notice to you.

Thanks, Xstream