The requirement for producing original documents in court is found in the Best Evidence Rule, which is also found in Rule 130 of the Rules of Court

"As such, the circumstances surrounding the fact that Mendoza bet on the eventual winning numbers of the 6/42 lotto were clearly established. Notably, the RTC and the CA characterized the various pieces of evidence offered by Mendoza as secondary evidence. We clarify this point. xxx"
"Verily, secondary evidence is resorted to when the original document is unavailable. The requirement for producing original documents in court is found in the Best Evidence Rule, which is also found in Rule 130 of the Rules of Court."
"The Best Evidence Rule does not apply to every case where a document is involved. As this Court clarified in Arceo Jr. v. People: 'the rule applies only where the content of the document is the subject of the inquiry. Where the issue is the execution or existence of the document or the circumstances surrounding its execution, the best evidence rule does not apply, and testimonial evidence is admissible."
"In this case, while it is the numbers in the ticket that would prove whether Mendoza indeed won the jackpot lotto prize, it is actually the existence of the ticket that is being assailed by the sweepstakes office. Essentially, the reason why it rejected the claim of Mendoza was because the ticket was damaged, and when a case was filed in court, the ticket was not presented in evidence."
"Whether the ticket bearing the numbers of the lotto indeed existed is an issue that does not require the application of the Best Evidence Rule. Hence, compliance with the rules on the presentation of secondary evidence does not apply. The testimonial evidence of Mendoza and his relatives, substantiated by records of the sweepstakes office itself, surrounding the fact that Mendoza entered a lotto bet and that the chosen numbers correspond to the winning lotto number were rightly admissible and given weight."
"We recognize the interest held by the sweepstakes office to conduct the lottery in a manner that upholds integrity and credibility. We likewise recognize that the 'no ticket, no payment' policy is intended to be a deterrent against fraudulent claims and, in turn, ensure the financial viability of PCSO. We do not agree, however, with the sentiment in the instant Petition that the payment of the jackpot prize to Mendoza is tantamount to a violation of its own rules. As we have discussed, the PCSO Rules itself reveals that the Lotto 6/42 does not contemplate a pre-determined 'winning ticket,' and so its presentation in a pristine state must not be the sole determinant for the payment of the prize."
Very interesting and worth noting, isn't it? Bear this in mind. You may need it someday.
The facts and quoted salient portions of the decision are from Philippine Charity Sweepstakes Office v Antonio Mendoza (G.R. No. 257849, 13 March 2023).