BLR,

Yes, the PTAB can continue the proceedings... take a look below. I did a search and found this. I believe its still valid information.

The Patent Trial and Appeal Board’s Discretion To Maintain A Proceeding After Petitioner Termination

http://www.ptab-blog.com/2015/10/20/when-joint-settlement-agreements-do-not-settle/

Under 37 CFR 42.74, parties to a trial before the Patent Trial and Appeal Board (PTAB) may mutually agree to terminate the proceeding. However, the PTAB is not a party to the settlement and may independently determine any question of jurisdiction, patentability, or Patent Office practice irrespective of the parties’ agreement to terminate.

Indeed, in select instances the PTAB has elected to continue the proceeding despite a joint motion to terminate by the Parties. For example, in Yahoo! Inc., v. CreateAds LLC.,IPR2014-00200 filed against U.S. Patent No. 5,535,320, the request to terminate with respect to the Petitioners was granted, yet the proceeding itself was not terminated.

The PTAB’s rationale for maintaining the proceeding was based, at least in part, on the timing of the joint motion to terminate (i.e., the issues had been fully briefed and oral argument was conducted before the parties moved to terminate the proceeding (IPR2014-00200, Paper 40 at 2). Additionally, the ’320 patent was the subject of over ten district court litigations which had been stayed pending the outcome of the IPR, suggesting that the PTAB’s decision to proceed reflected an interest in promoting judicial efficiency with respect to the related district court litigations. In any event, the PTAB continued theCreateAds trial to a final written decision, pursuant to 35 U.S.C. §§ 317(a) and 318(a), and ultimately held that all 20 claims of the patent were unpatentable.

Yet refusals to terminate tend to be the exception rather than the rule. For example, other PTAB panels have decided to terminate even after completion of briefing and oral argument. E.g. Clio USA Inc. v. The Procter & Gamble Co., IPR2013-00438, Paper 57.

But parties should not assume that a termination is simply to be had for the asking. A recent Order in Acxiom Corp. et al. v. Phoenix Licensing LLC, CBM2015-00134 (and related cases), Paper 15 reminds us that settlement practice is not necessarily a simple endeavor before the PTAB. Analogous provisions in 35 U.S.C. §§ 317(a) and 327(a) state that IPR and PGR proceedings shall be terminated with respect to any petitioner upon the joint request of the petitioner and the patent owner, unless the Office has decided the merits of the proceeding before the request for termination is filed. Sections 317(b) and 327(b) further require that settlement agreements be filed with the PTAB.

In Acxiom, the PTAB determined that although the joint motion to terminate stated the parties wish to settle the proceedings, the agreement produced to the PTAB did not clearly resolve the disputes since there was no explicit reference to the CBM reviews. Consequently, the PTAB ordered the parties to submit a Joint Statement addressing whether any such agreement(s) exist.

Accordingly, parties in a PTAB proceeding that wish to terminate without disturbing the status quo would be wise to submit the joint motion as early as possible, before the PTAB has invested significant time and resources. Cases settled before oral argument and especially before the close of evidence stand the best chance of bilateral termination. Also, it stands to reason that the stronger a Petitioner’s showing of unpatentability, the more inclined the PTAB would be to maintain the proceeding and issue a final written decision. Further, a patent owner’s assertion of the patent in district court litigation(s) may decrease the likelihood of the PTAB terminating the proceeding. Finally, the parties may wish to make the disposition of PTAB cases explicit within the settlement agreement and also to designate any financial implications within a settlement agreement contingent upon the PTAB’s termination of the proceeding prior to a final written decision.