Siemens's Administrator v. Sellers was a case heard by the United States Supreme Court in 1887. The case involved a dispute between the administrator of the estate of a deceased man, Siemens, and the defendant, Sellers. The administrator of the estate had brought a suit against Sellers for the recovery of a debt owed to Siemens. The administrator argued that the debt was secured by a mortgage on certain real estate owned by Siemens. The Supreme Court held that the administrator was entitled to recover the debt from Sellers. The Court found that the mortgage was valid and enforceable, and that the administrator was entitled to recover the debt from Sellers. The Court also held that the administrator was entitled to recover the debt from Sellers even though the mortgage had been assigned to another party. The Court reasoned that the assignment of the mortgage did not extinguish the debt, and that the administrator was still entitled to recover the debt from Sellers. In conclusion, the Supreme Court held that the administrator was entitled to recover the debt from Sellers. The Court found that the mortgage was valid and enforceable, and that the administrator was entitled to recover the debt from Sellers even though the mortgage had been assigned to another party.

In Siemens's Administrator v. Sellers, the Supreme Court was tasked with determining whether a contract between two parties that had been partially performed could be enforced in court. The majority opinion held that it could not, as the statute of frauds required contracts to be fully executed and signed by both parties before they were enforceable. However, Justice Field dissented from this decision on the grounds that partial performance should suffice for enforcement of a contract if there is evidence of an agreement between both parties and no other explanation for why one party would have gone through with their part of the deal without expecting something in return. He argued that such agreements should not be invalidated simply because they are not written down or signed; rather, courts should look at all available evidence when making decisions about enforcing contracts so long as doing so does not violate public policy or any other laws governing contractual relationships.