Short answer. Yes. Article 543 of the Civil Code provides that after partition, each participant is deemed to have exclusively possessed the portion allotted to them for the entire period of co-possession. The entire co-ownership period counts retroactively toward your prescriptive period, as if you had possessed that specific portion alone from the start.
What the law says
Each one of the participants of a thing possessed in common shall be deemed to have exclusively possessed the part which may be allotted to him upon the division thereof, for the entire period during which the co-possession lasted.
Civil Code, Article 543 — Possession in Common. Read the full provision →
How the retroactive rule works
Article 543 establishes a legal fiction that benefits co-possessors upon partition. Once the co-ownership ends and portions are divided, each person is deemed to have "exclusively possessed the part which may be allotted to him upon the division thereof, for the entire period during which the co-possession lasted." In practical terms: if you and siblings co-possessed land for twenty years and then partitioned it, and your share falls within the prescription requirement, the law treats you as having held your specific portion exclusively for those full twenty years — not merely from the date of partition.
Why this matters for prescription claims
Acquisitive prescription requires a period of continuous, public, and adverse possession. Without the rule in Article 543, a co-possessor might argue that their prescriptive period only began running at partition — potentially losing the benefit of years or decades of shared possession. Article 543 prevents this by back-counting the full co-possession period toward the share each person ultimately receives. If the combined period of co-possession and post-partition exclusive possession satisfies the required prescriptive period, the right is complete and can be formalized.
Interruption affects everyone
Article 543 also carries a risk that flows in the opposite direction. "Interruption in the possession of the whole or a part of a thing possessed in common shall be to the prejudice of all the possessors." If a third party successfully interrupted possession — by filing suit, by physical dispossession, or by any other legally recognized act of interruption — that interruption breaks the prescriptive period for every co-possessor, not just the one most directly affected. You cannot claim that the interruption only affected your co-owner's count while yours kept running.
Civil interruption follows the Rules of Court
Article 543 distinguishes between ordinary interruption and civil interruption, noting that for the latter, the Rules of Court apply. Civil interruption typically occurs through the filing of a judicial action. The procedural details — when filing interrupts, what must be served, whether a dismissed case revives the prescription period — are governed by those rules rather than by the Civil Code provision itself. If you are trying to calculate whether your prescriptive period has been interrupted, whether by an old lawsuit against the property or by some other legal action, the specific facts and timing will determine the answer.