The law was largely the result of Samuel R. Thurston, the Oregon territorial delegate to Congress. The act, which became law on September 27 1850, granted 160 acres (1.3 km²) to every unmarried white male citizen eighteen or older, and 320 acres (2.6 km²) to every married couple, arriving in the Oregon Territory before December 1, 1850. In the case of a married couple, the husband and wife each owned half in their own name. The law was one of the first that allowed married women in the United States to hold property under their own name. Half-blood Native Americans were also eligible for the grant. A provision in the law granted half the amount to those who arrived after the 1850 deadline but before 1854. Claimants were required to live on the land and cultivate it for four years to own it outright.
The provisional government formed at Champoeg had limited land claims in the hope of preventing land speculation. The Organic Act of the Oregon Territory had granted 640 acres (2.6 km²) to each married couple. The new law voided the previous statutes but essentially continued the same policy and was worded in such a way as to legitimize existing claims. One such claim legitimized by the act was that of George Abernethy, who had been elected to the governorship in the days of the provisional government. His claim became famous for Abernethy Green, where new emigrants camped at the end of the Oregon Trail while seeking a piece of land for themselves.
Claims under the law were granted at the federal land office in Oregon City. The most famous patent granted at the Oregon City land office was the plat for the city of San Francisco, which had to be sent up the coast from California by ship. The claims of the land were surveyed by the Surveyor General of Oregon, an office created out of the law. As part of the general survey, the Willamette Stone was placed just west of Portland, defining the Willamette Meridian.
After the 1854 cut-off date, land in Oregon was no longer free but was sold at a price of $1.25 an acre ($3.09/hectare) with a limit of 320 acres (1.3 km²) in any one claim. In the following years the price was raised and the maximum size of a claim was progressively lowered. In 1862 Congress passed the Homestead Act which was largely designed to encourage settlement on the Great Plains but applied to Oregon as well.