Every person having any interest, whether in possession or otherwise, who is not a plaintiff shall be made a defendant in such complaint.
17-103.Parties defendant.
Article XVII. Partition · Not amended since adoption on record · Last verified July 20, 2026
In one sentenceRequires every person with any interest in the land, whether in possession or not, who isn't already a plaintiff, to be named as a defendant in the partition complaint.
Full Text of 735 ILCS 5/17-103
Plain-English Summary
This section keeps the rule simple: anyone with an interest in the premises, whether that interest gives them possession or not, must be a defendant unless they're already a plaintiff. There's no middle category of interested person who can be left out.
That broad sweep works with the complaint requirements in the surrounding sections. Because the complaint must set out the known interests of tenants, remaindermen, and contingent beneficiaries, this section makes sure each of those same people ends up joined as a party, not merely described.
Frequently Asked Questions
Who must be named as a defendant in an Illinois partition action?
Every person having any interest in the premises, whether in possession or otherwise, who is not already a plaintiff.
Does a non-possessory interest, like a remainder or reversion, still require joinder as a defendant?
Yes. The section covers any interest, whether or not it carries possession.
Can an interested co-owner be left out of the case entirely?
No. The section requires that every interested person who isn't a plaintiff be made a defendant.
What if some interested parties' names are unknown to the plaintiff?
A related section addresses unknown parties and unknown or uncertain shares, letting the complaint state that fact instead.
Does this section apply only to co-owners of the fee?
No. It reaches every person with any interest in the premises, not only fee co-owners.
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
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