Del. Code tit. 10 § 8905
Where witness fees in any civil action instituted in New Castle County have been taxed and paid as part of the costs, and remain unclaimed for a period of 6 months from the date of payment thereof, the Prothonotary shall notify the witness at the witness's last known address by registered mail, return receipt requested, of the fact that the witness fee is being held for the witness, and must be claimed within a period of 6 months from the date of such notice. When any of the witness fees have remained unclaimed for a period of one year from the date of payment, the Prothonotary shall pay the unclaimed witness fees to the State Treasurer to be deposited to the credit of the general funds of the State. The Prothonotary's office may retain 15 percent of such unclaimed witness fees to defray the costs incident to carrying out the provisions of this section.
10 Del. C. § 8905