When an appeal is available
An applicant whose claims have been twice rejected may appeal to the Patent Trial and Appeal Board under § 134. In practice the trigger is usually a final rejection, though the statutory condition is the second rejection rather than finality as such.
The appeal is taken from the examiner's rejection of claims. It is not a route for reviewing objections or other petitionable matters, which follow a separate track. Sorting the appealable issues from the petitionable ones before filing avoids the most common structural problem with an appeal.
The sequence
Notice of appeal (§ 1204). Filed with the fee, within the period for reply. The notice does not identify the issues; it preserves the appeal and starts the clock for the brief.
Appeal brief (§ 1205). The substantive filing. Its required content is prescribed, and a brief omitting a required element is subject to a notification of non-compliance with a short window to correct. The most consequential drafting choice is claim grouping: claims argued together stand or fall together, so a claim whose separate patentability is not separately argued will not be considered separately by the Board.
Amendments and evidence after appeal (§ 1206). Entry is restricted at this stage. An amendment or affidavit filed after the appeal has been taken is admitted only in limited circumstances, which is why the record should be in the shape you want before the notice is filed.
Examiner's answer (§ 1207). The examiner responds, may withdraw rejections, and in some circumstances may designate a new ground of rejection — which gives the applicant a choice between reopening prosecution and maintaining the appeal.
Reply brief (§ 1208). Optional, and limited to responding to the answer rather than raising arguments that could have been made in the brief.
Decision (§ 1213). The Board affirms, reverses, or affirms in part, and may itself enter a new ground of rejection.
After the decision (§ 1214). What follows depends on the outcome: rehearing, reopening prosecution, or, where the rejection is affirmed, judicial review under § 1216.
What appeals turn on
The record, not new argument. The Board reviews the rejection on the record made before the examiner. Arguments not made below are generally not considered, and evidence not entered below is not in front of the Board.
Whether the examiner met the burden. Many successful appeals are not arguments that the invention is patentable in the abstract, but that the rejection as articulated fails — a missing factual finding, an unsupported assertion that an element is conventional, a claim limitation never addressed. The obviousness and eligibility sections matter here as much as the appeal chapter does.
Claim grouping. Worth repeating because it is the most common avoidable loss. If several rejected claims differ in ways that matter, each difference has to be argued separately and under its own heading, or the Board will decide the group on a representative claim.
Weighing an appeal against continued examination
An appeal is slow, and forwarding it to the Board carries a further fee at the reply-brief stage. Whether to appeal or file a request for continued examination is a strategic judgment that turns on how far apart the applicant and the examiner actually are. An appeal suits a clean legal disagreement about an articulated rejection. It suits poorly a situation that one more amendment would resolve, or one where the examiner's position rests on a factual finding the applicant could displace with evidence that has not yet been submitted.