Unified Patents is seeking prior art on claim 1 of US Patent No. 9,531,872. The patent is owned by Missed Call LLC, a DynaIP entity, which is an NPE. The '872 patent relates to a communication apparatus for providing an indication about a missed telephone call. It has been asserted against NEC, Twilio, TalkDesk, Mitel, and Freshworks. The link for litigation can be found here: https://portal.unifiedpatents.com/litigation/caselist?patents=9531872&sort=-filed_date APEX STANDARDS has shared prior US patent art, non-US patent art, and Non-Patent Literature art as well as corresponding claim charting against the patent. Interested professionals may take them and craft work product from there. The link can be found here: https://www.apexstandards.com/pcc/US9531872B2_construction/ https://www.apexstandards.com/pcc/US9531872B2_invalidity/ IPRally https://www.iprally.com is a patent research tool powered by modern Graph AI technology: technical information is converted into knowledge graphs corresponding how patent professionals perceive technology, and the AI is trained using Patent Examiner data to find similar documents. IPRally suits for prior art and state of the art searches of all types. Besides providing provenly relevant hits, IPRally’s explainable AI can also give reasons for them, speeding up the analysis (available in online tool). Fully automated prior art search results for the target patent are attached. Traindex is a machine learning enabled search service. They have provided an ordered list of most semantically similar patent documents. The results are filtered to include only results with the publication date preceding that of the patent being challenged. The link can be found here: https://www.traindex.io/prior-art/US-9531872-B2 Techson IP has provided its Full validity-focused Limestone|Report https://www.limestonereport.com/ which includes: a list of highly relevant prior art patent leads - individually ranked to the claims and tiered by research efficiency; summary predictive analytics about the search; a full CPC technology profile. Interested professionals may take them and craft work products from there. The Full Report link is here: https://s3.amazonaws.com/report.limestoneip.com/Ojh7_ghzDqkj8Ni3hOm4lc.full.html View the Similar Documents (patents + scholarly publications) generated by Google Patents: Patents: https://patents.google.com/?q=~patent%2fUS9531872B2&before=filing:20100721 NPL: https://patents.google.com/?q=~patent%2fUS9531872B2&before=filing:20100721&patents=false&scholar ** PLEASE READ THE RULES FOR THIS CONTEST BEFORE YOU DECIDE TO PARTICIPATE. ** ** TO QUALIFY FOR CONSIDERATION, A CLAIM CHART IS REQUIRED. ** ** PLEASE USE THE PROVIDED CLAIM CHART AS A TEMPLATE ** ** PRIOR ART THAT HAS BEEN PREVIOUSLY CITED DURING PROSECUTION WILL NOT BE CONSIDERED. **