The general liability risk within the United States is low but it's necessary to review the laws and decisions of all other countries because the extraterritorial application of laws to content hosted in the US is a significant concern.
Immunity under Section 230 requires that: (1) the defendant is a provider or user of an interactive computer service; (2) the cause of action treat the defendant as a publisher or speaker of information; and (3) the information at issue be provided by another information content provider. Zeran, 129 F.3d at 330. Even completely ignoring a complaint has generally been found not to garner liability, so protection appears to be very comprehensive, though it still doesn't stop people from trying.
In 2002, the California Court of Appeal held that CDA Section 230 does not apply to distributor liability, meaning that a defendant who had notice of a defamatory statement must stop publishing it or face liability. Barrett v. Rosenthal, 114 Cal. App.4th 1379 (2002). The California Supreme Court, in a unanimous decision overturned, holding that Rosenthal was a "user of interactive computer services" and therefore immune from liability under Section 230. See also Grace v. eBay, Inc., 2004 WL 1632047 (Cal. Ct. App. Jul. 22, 2004) (no immunity against liability for a distributor of information who knew or had reason to know that the information was defamatory). Grace v. eBay was resolved without an opinion. The lower courts in Grace and Barrett had reached opposite conclusions when they were appealed to the California Supreme Court. In taking these cases, it was deciding to uphold or reverse Blumenthal v. AOL. Blumenthal, noted the conference report comment that the clear intent of the CDA was to overrule the state decision in Stratton-Oakmont v. Prodigy and opined that accepting distributor liability would expose them to liability that Congress had clearly intended to protect them from.
The CDA does not "limit or expand any law pertaining to intellectual property" 47 U.S.C. Section 230(e)(2); see also Gucci America, Inc. v. Hall & Associates, 135 F. Supp. 2d 409 (S.D.N.Y. 2001) (no immunity for contributory liability for trademark infringement); Perfect 10, Inc. v CCBill LLC (No. CV 02-7624 LGB) (C.D. Cal. 22 June 2004) (state right of publicity claim is not covered by Section 230); but see Carafano v. Metrosplash.com, Inc., 339 F.3d 1119 (9th Cir. 2003) (dismissing, inter alia, right of publicity claim under Section 230 without discussion).
Courts have not yet addressed whether a state law trade secret claim is a "law pertaining to intellectual property."
The OCILLA can provide a safe harbor for OSPs who comply with its requirements. As noted above, CDA Section 230 does not provide protection against a copyright claim.