SAN FRANCISCO - The National Bureau of Unseated Enzymes will not seat a discovery filing for array-associated reverse transcriptases until a red FUNCTION UNKNOWN stamp sits overnight on the cover sheet and a paper strip reading CRISPR-LIKE REPEATS is taped to the duty window. On 23 September 2026, Anthropic said Claude agents found a previously uncharacterized bacteriophage enzyme system it calls array-associated reverse transcriptases, or ART. About 950 agents searched a large DNA database for reverse transcriptases for 21 hours and used about 210 million tokens after a human prompt. ART has three parts: a reverse transcriptase, a partner gene, and a long array of evenly spaced DNA repeats like a CRISPR array. Early lab tests show the array is expressed as distinct short RNAs. Anthropic said it does not yet know the system's function. The enzyme had been identified in earlier studies. Claude appears to have been first to connect the array and the partner gene. The work is a preprint and has not been peer reviewed. Human scientists did the wet lab work. The Bay Area lab is rated BSL-1/2 and handles no human pathogens. "Packets that call ART the next CRISPR return as notes. The stamp sits overnight and the strip stays on the window," a duty clerk said. A clerk at a South San Francisco sequencing desk said the desk's packet came back as a note on Friday because the cover sheet had called ART the next CRISPR. The bureau said seating can happen the morning after the stamp has sat, if the strip is still on the glass.