The constructive or implied easements that Polycarp refers to are easements disclosed by an inspection of the land. An adjoining parcel owner may be using an easement on the subject land, and that need not be recorded. It could be an easement by necessity if the adjoining owner is landlocked.
Utility easements need not be statutory only. An owner may grant an easement for necessary utilities. Most often, when the plat for the subdivision is laid out and recorded, the easements will be shown on the plat.
Another problem for purchasers is a possible judgment against any previous owner while that previous owner had a judgment rendered against him. Judgments are liens for 7 years in Illinois, but can be renewed twice. No memo of judgment need be recorded. The mere entry in the clerk’s records is enough notice. Hence, a title company has some employees going through the court’s records every day for judgments that could affect property. This becomes a problem when the previous owner’s name is John Doe. The title company accepts an affidavit that he is not that John Doe. Under the Torrens system, the memorandum of the judgment must be filed for it to be a lien. Some attorneys also file a memo in the Recorder’s Office, for non-Torrens property, but that is not necessary.
If, however, there is a pending equity action affecting the property specifically (such as a partition suit, suit to quiet title, suit for an easement of necessity, etc.) a lis pendens notice must be recorded to give notice of the pending procedings.
Let me emphasize that in Illinois, an instrument when recorded is returned to the party. If it is filed in Torrens, it is not. In SC, however, the Recorder’s Office is called the Registrar of Mesne Conveyances.
You can build on an easement if the building does not interfere with the easement.
When the state of Illinois acquired those lands from the federal government (which were not previously conveyed), it deeded certain townships (a six-mile square, six by six sections) to the Canal Commissioners and the School Trustees. It also deeded (or granted an easement?) to railroad companies. Under the common law, the municipality acquired only an easement to platted roads, but if the plat conforms to the Plat Act (enacted in 1834), the municipality acquired the fee. This became an issue in downtown Chicago, as to whether the City acquired the fee to a platted street (such as Monroe St.) or merely had an easement. In one case, a bank convinced the Illinois SC that the city only had an easement for Monroe St. because one of the school commissioners (section 16 in every township was reserved for a school and conveyed to the school commissioners), neglected to sign it, a necessary requirement under the Act. The commissioner corrected that error and signed it before the suit was filed, but the Court held that did not retroactively make the plat conform. However, in a similar suit filed in a canal trustee’s plat, the Court held that the city had title even though the plat did not have the seal of the county surveyor, also a necessary requirement. (I may have the respective state agencies reversed.) Anyway, the Court held that the city had title to a certain downtown street and that the adjoining owners have to pay an annual premium to maintain overhead passageways and under the street storage facilities. But the First National Bank was successful in its suit as to the title of the street and was able to build overhead passageways without cost.
The Prudential Building in downtown Chicago is built over the Illinois Central’s property (?) The IC deeded the air rights to the Prudential so it could construct the building. A tax payer brought a suit, contending that the state conveyed only an easement to the IC. The Illinois SC in a landmark decision held estoppel against the state because for many years it treated the IC as the owner. I don’t think estoppel against a state has ever otherwise been upheld.