(770 ILCS 60/11) (from Ch. 82, par. 11)
    Sec. 11. Averments in pleading; parties; dismissal; notice.
    (a) Any pleading asserting a claim for lien shall contain (i) a brief statement of the contract or contracts to which the person (hereinafter called the "claimant") asserting a claim for lien in the pleading is a party and by the terms of which the claimant is employed to furnish lienable services or material for the real property (herein called the "premises"), (ii) the date when the contract or contracts were dated or entered into, (iii) the date on which the claimant's work, labor or material labor, services, material, fixtures, apparatus or machinery, forms or form work was last performed or furnished, whether the claimant completed furnishing or performing its work, labor and material labor, services, material, fixtures, apparatus or machinery, forms or form work and if not why, (iv) the amount due and unpaid to the claimant, (v) a description of the premises, and (vi) such other facts as may be necessary for a full understanding of the rights of the parties. Where plans and specifications are by reference made a part of a contract that is required to be alleged in a pleading, it shall not be necessary to set the same out in the pleading or attached as exhibits, but the same may be produced on the trial of the suit. It shall not be necessary to include a statement of any contract to which the claimant is not a contracting party.
    (b) Each claimant shall make as parties to its pleading (hereinafter called "necessary parties") the owner of the premises, the contractor, all persons in the chain of contracts between the claimant and the owner, all persons who have asserted or may assert liens against the premises under this Act, and any other person against whose interest in the premises the claimant asserts a claim.
    (c) Necessary parties whose claims or interests are not disclosed by a document recorded at the time a proper lis pendens of the action under Section 2-1901 of the Code of Civil Procedure has been recorded (or if the action is instituted as a mortgage foreclosure at the time a proper notice of foreclosure under Section 15-1503 of the Code of Civil Procedure has been recorded) may be named and made parties under the description of "unknown necessary parties". Persons other than unknown necessary parties who may be interested in the premises but whose identities are unknown to the claimant may be named and made parties to the action under the description of "unknown owners".
    (d) A claimant may, in its, his or her discretion, make as parties (hereinafter called "permissible parties") to the action any other persons having a legal, equitable or possessory interest in or claim to the whole or any part of the premises, but failure to make any such permissible party a party to the action shall not defeat the lien, but the claim of each claimant asserting a lien claim under this Act in the action shall be subject to the interest of such permissible party not made a party, and the action shall not adversely affect the interest of any such permissible party not made a party and not served with notice by summons or publication in the action as provided in this Act.
    (e) The plaintiff shall cause notice to be given to all such necessary parties or cause them to be served by summons or by publication in like manner and upon the same conditions as in other civil actions, and the plaintiff's failure to do so, shall be grounds for judgment against him, her, or it on the merits. A claimant other than the plaintiff asserting a claim in the action under this Act shall also cause notice to be given to or cause summons to be served upon any necessary parties who have not been joined to the action, and his, her, or its failure to do so shall be grounds for judgment against him, her or it on the merits. Process may issue and service by publication may be had against those persons so named under the descriptions of "unknown necessary parties" or "unknown owners", and judgments entered against them shall be of the same effect as though they had been designated by and served under their proper names, provided that any judgment shall only bind any person served by publication with respect to their interests in the premises and liens asserted or assertable against the premises under this Act. A person who has been properly served in the action by summons or by publication by any claimant shall be deemed properly served by all claimants in the action regardless of whether such persons have been served before or after such claimants or any of them shall have appeared, filed their pleadings or become parties to the action, provided that nothing in this Section 11 shall excuse a claimant from joining all necessary parties to the claimant's pleading, whether as named parties, unknown necessary parties, or unknown owners, within the time permitted by this Act. Nothing in this Section 11 shall prevent service by publication in any proceeding brought under this Act where authorized by this Act in like manner and upon the same conditions as in other civil actions.
    (f) Any necessary party or permissible party who has not been joined to the action under his, her, or its proper name, may, upon application of such party to the court wherein the action is pending, be made or become a party at any time before final judgment, but such joinder shall not give such party any substantive rights not otherwise provided by law, or excuse failure to comply with the provisions of any applicable law.
    (g) No action under the provisions of this Act shall be voluntarily dismissed by the party bringing it without due notice to all parties to the action, and upon leave of court for good cause shown and upon terms approved by the court.
(Source: P.A. 94-627, eff. 1-1-06.)