The vial was initially stored in the refrigerator on 09-Mar-2023 and administered after manufacturer expiry(11-Feb-2023); No adverse event; 6 patients received expired Monovalent 6M-5Y doses of Moderna COVID-19 vaccine; This spontaneous case was reported by a nurse and describes the occurrence of EXPIRED PRODUCT ADMINISTERED (6 patients received expired Monovalent 6M-5Y doses of Moderna COVID-19 vaccine), PRODUCT STORAGE ERROR (The vial was initially stored in the refrigerator on 09-Mar-2023 and administered after manufacturer expiry(11-Feb-2023)) and NO ADVERSE EVENT (No adverse event) in a child patient of an unknown gender who received mRNA-1273 (Moderna COVID-19 Vaccine) (batch no. AR9236B) for COVID-19 prophylaxis.     No Medical History information was reported.    On 09-Mar-2023, the patient received dose of mRNA-1273 (Moderna COVID-19 Vaccine) (unknown route) 1 dosage form. On 09-Mar-2023, the patient experienced EXPIRED PRODUCT ADMINISTERED (6 patients received expired Monovalent 6M-5Y doses of Moderna COVID-19 vaccine). On an unknown date, the patient experienced PRODUCT STORAGE ERROR (The vial was initially stored in the refrigerator on 09-Mar-2023 and administered after manufacturer expiry(11-Feb-2023)) and NO ADVERSE EVENT (No adverse event). At the time of the report, EXPIRED PRODUCT ADMINISTERED (6 patients received expired Monovalent 6M-5Y doses of Moderna COVID-19 vaccine), PRODUCT STORAGE ERROR (The vial was initially stored in the refrigerator on 09-Mar-2023 and administered after manufacturer expiry(11-Feb-2023)) and NO ADVERSE EVENT (No adverse event) outcome was unknown.        For mRNA-1273 (Moderna COVID-19 Vaccine) (Unknown), the reporter considered NO ADVERSE EVENT (No adverse event) to be not related. No further causality assessments were provided for EXPIRED PRODUCT ADMINISTERED (6 patients received expired Monovalent 6M-5Y doses of Moderna COVID-19 vaccine) and PRODUCT STORAGE ERROR (The vial was initially stored in the refrigerator on 09-Mar-2023 and administered after manufacturer expiry(11-Feb-2023)).    No concomitant medications were reported.  A nurse was called to report that 6 patients received expired monovalent 6M-5Y doses of Moderna COVID-19 vaccine after 11FEB2023. The case involved a combination of the first dose and some 2nd primary doses. Lot number was reported as AR9236B with MFG Exp. Date: 11FEB2023 The intact carton and vial size were reported as unknown. 1 vial was initially stored in the refrigerator on 16-FEB-2023, 1 vial on 02MAR2023, and 1 vial on 09MAR2023. The vaccine was administered to one patient on 16Feb2023, two patients on 02Mar2023, and three patients on 09Mar2023. The vial did not undergo any temperature excursions.  No treatment medications were reported.  This case contains information for the 4th patient out of 6 child patients as described by the reporter.   This case was linked to US-MODERNATX, INC.-MOD-2023-715544, US-MODERNATX, INC.-MOD-2023-715545, US-MODERNATX, INC.-MOD-2023-715548, US-MODERNATX, INC.-MOD-2023-715551, US-MODERNATX, INC.-MOD-2023-715550 (E2B Linked Report).; Sender's Comments:  US-MODERNATX, INC.-MOD-2023-715544:Patient 01 (Master case) US-MODERNATX, INC.-MOD-2023-715545:Patient 2 US-MODERNATX, INC.-MOD-2023-715548:Patient 6 US-MODERNATX, INC.-MOD-2023-715551:Patient 5 US-MODERNATX, INC.-MOD-2023-715550:Patient 3