When there are any persons interested in the premises whose names are unknown, or the share or quantity of interest of any of the parties is unknown to the plaintiff, or such share or interest is uncertain or contingent, or the ownership of the inheritance depends upon an executory devise, or the remainder is contingent, so that such parties cannot be named, it shall be so stated in the verified complaint.
17-104.Unknown parties.
Article XVII. Partition · Not amended since adoption on record · Last verified July 20, 2026
In one sentenceAllows a partition complaint to state that certain parties, shares, or interests are unknown, uncertain, or contingent, rather than naming and quantifying them, when the plaintiff doesn't have that information.
Full Text of 735 ILCS 5/17-104
Plain-English Summary
Partition often involves land passed down over generations, and a plaintiff cannot always identify or quantify every interest with precision. This section lets the complaint say so. It covers people interested in the premises whose names are unknown, shares or interests that are unknown to the plaintiff, and interests that are uncertain or contingent.
It also covers two title-specific situations: when ownership of the inheritance depends on an executory devise, or when a remainder is contingent, so that the parties holding those interests cannot presently be named. In any of these situations, the complaint states the condition rather than pretending to a certainty the plaintiff doesn't have.
Frequently Asked Questions
Can a partition complaint be filed if some co-owners' names are unknown?
Yes. The complaint may state that fact when the names of interested persons are unknown to the plaintiff.
What if the plaintiff doesn't know the exact share each party owns?
The complaint may state that the share or quantity of interest is unknown, uncertain, or contingent.
What is meant by an interest depending on an executory devise?
The section covers cases where ownership of the inheritance depends on an executory devise, so the eventual owner cannot yet be named with certainty.
Does a contingent remainder prevent a partition action from moving forward?
No. The complaint may state that the remainder is contingent and that the holder cannot presently be named.
Does this section replace the requirement to name known parties?
No. It applies only where names, shares, or interests cannot be stated with certainty, alongside the general requirement to describe known interests.
Amendment History
(Source: P.A. 82-280.)
Source & verification. Section text and amendment history are
reproduced verbatim from the Illinois Compiled Statutes, published by the
Illinois Compiled Statutes, Illinois General Assembly / Legislative Reference Bureau. Last verified July 20, 2026.
· Official source
Also known as: unknown heirs partition action illinoisunknown parties in illinois partition lawsuitcontingent remainder partition illinoisexecutory devise partition complaint illinois