import re
pattern = r"^\d+/\d+/\d+ .*(?:\n(?!^\d+/\d+/\d+ ).*)*"
s = ("05/06/21 05/06/21 Margin Div/Int - Income ACTIVISION BLIZZARD INC\n\n"
"COM\n"
"Payable: 05/06/2021\n"
"QUALIFIED DIVIDENDS 23.50 \n\n"
"ATVI - 0.00 23.50 (9,425.77)\n\n"
"05/13/21 05/13/21 Margin Div/Int - Income APPLE INC\n"
"COM\n"
"Payable: 05/13/2021\n"
"QUALIFIED DIVIDENDS 6.16 \n\n"
"AAPL - 0.00 6.16 (9,419.61)\n\n"
"05/28/21 05/28/21 Margin Div/Int - Income STARBUCKS CORP\n"
"COM\n"
"Payable: 05/28/2021\n"
"QUALIFIED DIVIDENDS 18.00 \n\n"
"SBUX - 0.00 18.00 (9,401.61)\n\n"
"05/28/21 05/28/21 Margin Div/Int - Expense MARGIN INTEREST CHARGE\n"
"Payable: 05/28/2021 \n\n"
" - - 0.00 (73.03) (9,474.64)")
print(re.findall(pattern, s, re.M))
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
['05/06/21 05/06/21 Margin Div/Int - Income ACTIVISION BLIZZARD INC\n\nCOM\nPayable: 05/06/2021\nQUALIFIED DIVIDENDS 23.50 \n\nATVI - 0.00 23.50 (9,425.77)\n', '05/13/21 05/13/21 Margin Div/Int - Income APPLE INC\nCOM\nPayable: 05/13/2021\nQUALIFIED DIVIDENDS 6.16 \n\nAAPL - 0.00 6.16 (9,419.61)\n', '05/28/21 05/28/21 Margin Div/Int - Income STARBUCKS CORP\nCOM\nPayable: 05/28/2021\nQUALIFIED DIVIDENDS 18.00 \n\nSBUX - 0.00 18.00 (9,401.61)\n', '05/28/21 05/28/21 Margin Div/Int - Expense MARGIN INTEREST CHARGE\nPayable: 05/28/2021 \n\n - - 0.00 (73.03) (9,474.64)']