As it has been posted before there are mamy types of mergers:
MERGER
n. 1) in corporate law, the joining together of two corporations in which one corporation transfers all of its assets to the other, which continues to exist. In effect one corporation "swallows" the other, but the shareholders of the swallowed company receive shares of the surviving corporation. A merger is distinguished from a "consolidation," in which both companies join together to create a new corporation. 2) in real property law, when an owner of an interest in property acquires a greater or lesser interest in the same property, the two interests become one. Examples: a person with a life estate is given the title to the property by inheritance, the life estate is merged with the titled interest. 3) another important form of merger occurs when a person acquires two parcels of land which were once a single lot that had been divided into two lots by a "lot split" granted by the city or county. If the minimum lot size has been increased by changes in local ordinances and the two lots are now sub-standard size, the buyer who acquires title in the two lots may find that they are "merged" into one lot and he or she has lost the right to build a house on each lot. To avoid this problem, the buyer should make sure title in each lot is obtained under a different name, i.e. husband taking one, and wife the other.
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