Better known as the "Twenty N[word] Law", Congress ammended the limit of slaves needed to exempt one overseer several times, the last change being made on May 11, 1865. On May 1, 1863, the law was revised to include only farms operated by dependents, minors, men of unsound mind, single women and soldiers in field service. The owner had to pay $500 to the Confederate government. He or she also had to provide an affidavit that an overseer otherwise exempt from military service could not be found, and that the man hired had been an overseer prior to April 16, 1862.

On Feb. 17, 1864, the limit of slaves was revised downward to fifteen. The Bureau of Conscription later ruled that fifteen slaves could come from two different farms, so long as the property was contiguous and both farm owners execute a joint bond. However, the fifteen slaves had to be at least sixteen years of age, and not older than fifty. Previously there had been stipulations regarding age of slaves.

According to the new law, slave owners were required to furnish the government with 100 pounds of bacon, or 200 pounds of beef and pork. In addition, they would agree to sell any marketable surplus to families of soldiers or a government agent at prices set by local commissioners.

My source is Conscription and Conflict in the Confederacy by Albert Burton Moore, 1924.