4 Pa. Code § 137.6 – Effect.

(a) A caveat entered against the granting of a warrant on an application on file shall bar the issuing of the warrant except when:
1. (1) The caveator is deemed to have abandoned his objections.
2. (2) The caveator has not shown proof in support of his claim.
3. (3) The Board dismisses the caveat, after determination or hearing upon a citation.
(b) A caveat, note on survey or writing in the nature of a caveat may not continue to bar the issuing of a patent to the person against whom the caveat is entered longer than 2 years, unless the parties interested in the land takes out a citation within the 2-year period to bring the dispute to a decision and prosecute the same to effect.