Wis. Stat. § 32.10
If any property has been occupied by a person possessing the power of condemnation and if the person has not exercised the power, the owner, to institute condemnation proceedings, shall present a verified petition to the circuit judge of the county wherein the land is situated asking that such proceedings be commenced. The petition shall describe the land, state the person against which the condemnation proceedings are instituted and the use to which it has been put or is designed to have been put by the person against which the proceedings are instituted. A copy of the petition shall be served upon the person who has occupied petitioner's land, or interest in land. The petition shall be filed in the office of the clerk of the circuit court and thereupon the matter shall be deemed an action at law and at issue, with petitioner as plaintiff and the occupying person as defendant. The court shall make a finding of whether the defendant is occupying property of the plaintiff without having the right to do so. If the court determines that the defendant is occupying such property of the plaintiff without having the right to do so, it shall treat the matter in accordance with the provisions of this subchapter assuming the plaintiff has received from the defendant a jurisdictional offer and has failed to accept the same and assuming the plaintiff is not questioning the right of the defendant to condemn the property so occupied.
Wis. Stat. § 32.10
A cause of action under this section arises prior to the actual condemnation of the property if the complaint alleges facts that indicate the property owner has been deprived of all, or substantially all, of the beneficial use of the property. Howell Plaza, Inc. v. State Highway Comm. 66 Wis. 2d 720, 226 N.W.2d 185 (1975). In order for the petitioner to succeed in the initial stages of an inverse condemnation proceeding, the petitioner must allege facts that, prima facie, at least show there has been either an occupation of its property, or a taking, which must be compensated under the terms of the Wisconsin Constitution. Howell Plaza, Inc. v. State Highway Commission, 66 Wis. 2d 720, 226 N.W.2d 185 (1975). A landowner's petition for inverse condemnation, like a municipality's petition for condemnation, is not subject to demurrer. Revival Center Tabernacle of Battle Creek v. Milwaukee, 68 Wis. 2d 94, 227 N.W.2d 694 (1975). A taking occurred when a city refused to renew a lessee's theater license because of a proposed renewal project encompassing the theater's location, not when the city made a jurisdictional offer. Property is valued as of the date of the taking. Maxey v. Redevelopment Authority of Racine, 94 Wis. 2d 375, 288 N.W.2d 794 (1980). The doctrine of sovereign immunity cannot bar an action for just compensation based on the taking of private property for public use even though the legislature has failed to establish specific provisions for the recovery of just compensation. Zinn v. State, 112 Wis. 2d 417, 334 N.W.2d 67 (1983). A successful plaintiff in an inverse condemnation action was entitled to litigation expenses, which included expenses related to a direct condemnation action. Expenses related to an allocation proceeding under s. 32.11 were not recoverable. Maxey v. Racine Redevelopment Authority, 120 Wis. 2d 13, 353 N.W.2d 812 (Ct. App. 1984). The owner of property at the time of a taking is entitled to bring an action for inverse condemnation and need not own the property at the time of the commencement of the action. Riley v. Town of Hamilton, 153 Wis. 2d 582, 451 N.W.2d 454 (Ct. App. 1989). A constructive taking occurs when government regulation renders a property useless for all practical purposes. Taking jurisprudence does not allow dividing the property into segments and determining whether rights in a particular segment have been abrogated. Zealy v. City of Waukesha, 201 Wis. 2d 365, 548 N.W.2d 528 (1996), 93-2831. This section does not govern inverse condemnation proceedings seeking just compensation for a temporary taking of land for public use. Such takings claims are based directly on Article I, section 13, of the constitution. Anderson v. Village of Little Chute, 201 Wis. 2d 467, 549 N.W.2d 561 (Ct. App. 1996), 95-1677. The reversal of an agency decision by a court does not convert an action that might otherwise have been actionable as a taking into one that is not. Once there has been sufficient deprivation of the use of property there has been a taking even though the property owner regains full use of the land through rescission of the restriction. Eberle v. Dane County Board of Adjustment, 227 Wis. 2d 609, 595 N.W.2d 730 (1999), 97-2869. When a regulatory taking claim is made, the plaintiff must prove that: 1) a government restriction or regulation is excessive and therefore constitutes a taking; and 2) any proffered compensation is unjust. Eberle v. Dane County Board of Adjustment, 227 Wis. 2d 609, 595 N.W.2d 730 (1999), 97-2869. A claimant who asserted ownership of condemned land, compensation for which was awarded to another as owner with the claimant having had full notice of the proceedings, could not institute an inverse condemnation action because the municipality had exercised its power of condemnation. Koskey v. Town of Bergen, 2000 WI App 140, 237 Wis. 2d 284, 614 N.W.2d 845, 99-2192. The state holds title to the waters of the state and any private property interest in constructing facilities in those waters is encumbered by the public trust doctrine. A riparian owner does not have a right to unfettered use of the bed of the waterway or to the issuance of a permit to construct a structure, which weighs against a finding that a riparian owner suffered a compensable regulatory taking as the result of a permit denial. R.W. Docks & Slips v. State, 2001 WI 73, 244 Wis. 2d 497, 628 N.W.2d 781, 99-2904. Taking jurisprudence does not divide a single parcel into discrete segments and attempt to determine whether rights in a given piece have been entirely abrogated but instead focuses on the extent of the interference with rights in the parcel as a whole. R.W. Docks & Slips v. State, 2001 WI 73, 244 Wis. 2d 497, 628 N.W.2d 781, 99-2904. In order to state a claim of inverse condemnation under this section, the facts alleged must show either that there was an actual physical occupation by the condemning authority or that a government-imposed restriction deprived the owner of all, or substantially all, of the beneficial use of his or her property. E-L Enterprises, Inc. v. Milwaukee Metropolitan Sewerage District, 2010 WI 58, 326 Wis. 2d 82, 785 N.W.2d 409, 08-0921. A taking occurs in airplane overflight cases when government action results in aircraft flying over a landowner's property low enough and with sufficient frequency to have a direct and immediate effect on the use and enjoyment of the property. The government airport operator bears responsibility if aircraft are regularly deviating from FAA flight patterns and those deviations result in invasions of the superadjacent airspace of neighboring property owners with adverse effects on their property. Placing the burden on property owners to seek enforcement against individual airlines or pilots would effectively deprive the owners of a remedy for such takings. Brenner v. City of New Richmond, 2012 WI 98, 343 Wis. 2d 320, 816 N.W.2d 291, 10-0342. In order to constitute a taking, the property loss at issue must be the result of government action. The court is not free to disregard this plainly stated rule and search for inaction that might be considered to be the functional equivalent of action, as might be at issue for example in the negligence context. Fromm v. Village of Lake Delton, 2014 WI App 47, 354 Wis. 2d 30, 847 N.W.2d 845, 13-0014. Section 84.25(3) authorizes DOT to change access to a highway designated as controlled access in whatever way it deems "necessary or desirable." In controlled-access highway cases, abutting property owners are precluded from compensation for a change in access under s. 32.09(6) (b) as a matter of law. However, exercises of the police power cannot deprive the owner of all or substantially all beneficial use of the property without compensation. If the replacement access is so circuitous as to amount to a regulatory taking of the property, compensation is due and the abutting property owner may bring an inverse condemnation claim under this section. Provision of some access preserves the abutting property owner's controlled right of access to the property. Reasonableness is not the standard to apply to determine if compensation is due under s. 32.09(6) (b). Hoffer Properties, LLC v. State of Wisconsin, 2016 WI 5, 366 Wis. 2d 372, 874 N.W.2d 533, 12-2520. It has long been settled that constitutional takings provisions interpose no barrier to the exercise of the police power of the state. Injury to property resulting from the exercise of the police power of the state does not necessitate compensation. A state acts under its police power when it regulates in the interest of public safety, convenience, and the general welfare of the public. The protection of public rights may be accomplished by the exercise of the police power unless the damage to the property owner is too great and amounts to a confiscation. Claims for such "regulatory takings" must be brought under this section. Hoffer Properties, LLC v. State of Wisconsin, 2016 WI 5, 366 Wis. 2d 372, 874 N.W.2d 533, 12-2520.