> ## Documentation Index > Fetch the complete documentation index at: https://hedera-0c6e0218-mintlify-bc559771.mintlify.site/llms.txt > Use this file to discover all available pages before exploring further. # ThresholdKey > ThresholdKey is the Hedera protobuf message defining an N-of-M signing policy where any N of the listed public keys may authorize a transaction. A set of public keys that are used together to form a threshold signature. If the threshold is N and there are M keys, then this is an N of M threshold signature. If an account is associated with ThresholdKeys, then a transaction to move cryptocurrency out of it must be signed by a list of M signatures, where at most M-N of them are blank, and the other at least N of them are valid signatures corresponding to at least N of the public keys listed here. | Field | Type | Description | | ----------- | ---------------------------------------------------- | ------------------------------------------------------------- | | `threshold` | ​ | A valid signature set must have at least this many signatures | | `keys` | ​[KeyList](/reference/protobuf/basic-types/keylist)​ | List of all the keys that can sign | ####