Why was there controversy over the size of the Maxwell land grant?

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Explanation:

The Maxwell Land Grant, also known as the Beaubien-Miranda Land Grant, was a 1,714,765-acre Mexican land grant in Colfax County, New Mexico and part of adjoining Las Animas County, Colorado. This 1841 land grant was one of the largest contiguous private landholdings in the history of the United States. The New Mexico towns of Cimarron, Colfax, Dawson, Elizabethtown, French, Lynn, Maxwell, Miami, Raton, Rayado, Springer, Ute Park and Vermejo Park, came to be located within the grant, as well as numerous other towns that are now ghost towns.

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