"maintain a copy" is a correct phrase and can be used in written English.
It means to preserve or keep a duplicate version of something. Example: It is important to maintain a copy of all important documents in case the original is lost or damaged.
The credit repair organization shall maintain a copy of the statement signed by the consumer acknowledging receipt of the statement.
Failure to write or maintain a copy of the SSM plan is a deviation from the requirements of this subpart.
The Attorney General or a designee of the Attorney General shall maintain a copy of a certification made under this subsection.
The applicants for this appendix shall maintain a copy of the applicable generic DCD that includes all generic changes to Tier 1, Tier 2, and the generic technical specifications and other operational requirements.
The applicant for the ESBWR design shall maintain a copy of the aircraft impact assessment performed to comply with the requirements of 10 CFR 50.150(a) for the term of the certification (including any period of renewal).
The applicant for this appendix shall maintain a copy of the generic DCD that includes all generic changes it makes to Tier 1 and Tier 2, and the generic TS and other operational requirements.
Each party, or "node," participating in the blockchain network maintains a copy of the distributed ledger and acts as a "witness" to each transaction.
Three are stores of public genomes that Google maintains a copy of, and one is at a software company called Curoverse in Boston (see "Google Wants to Store Your Genome").
Gliffy maintains a copy each time a document is saved, so you will never run the risk of losing any changes.
Because the blockchain is constantly monitored by the entire network of nodes, each of which maintains a copy of the blockchain, malicious users have no means of inserting fraudulent blocks into the public ledger without immediately being noticed by others.
NCHS maintains a copy of the combined data file and provides access to this file through the NCHS Research Data Center.
