Prior art

The USPTO database (via Google Patents, which aggregates USPTO data) lists the following "Cited by" references for US Patent 8904194. It's important to note that a "Cited by" reference indicates that a later patent cited US8904194, not that US8904194 cited it as prior art. To find prior art for US8904194, we need to look at the "Prior Art Citations" section of US8904194 itself.

Based on the full patent text provided for US8904194, the "Prior Art References" section is usually where these citations would be found. However, in the provided text, there is no explicit section titled "Prior Art References" or "U.S. Patent Documents" that typically lists the examiner-cited prior art. The "Prior art keywords" and "Prior art date" are general descriptive metadata, not specific patent citations.

To fulfill the request, I need to look for the "Cited Patent References" or "Other References" section within the actual patent document US8904194. Since the provided text is a full patent text and does not contain this section, I will explicitly state this and explain how prior art would typically be identified for anticipation claims.

Clarification on Prior Art and Anticipation (35 U.S.C. § 102):
Under 35 U.S.C. § 102, a patent claim is "anticipated" if every element of the claimed invention is found, either expressly or inherently described, in a single prior art reference that existed before the effective filing date of the claimed invention. The prior art reference must disclose exactly what is claimed, with the elements arranged as in the claim.

Since the full patent text provided does not explicitly list the prior art documents cited during the prosecution of US8904194, I cannot identify specific references to analyze for potential anticipation under 35 U.S.C. § 102.

To conduct a thorough prior art analysis for US8904194, one would typically obtain the official patent document from the USPTO and review the "References Cited" section, which lists both U.S. Patent Documents and Other Publications considered by the examiner.