Around 30,000 Frankfurt fans gained entry to Camp Nou last Thursday despite only officially receiving 5,000 tickets. Thousands more, though, were able to purchase seats in the home end, creating an even split among the 79,000 crowd.
The president blamed club members for selling their seats, the ticketing system -- which was inherited from the previous board -- and tour operators for abusing their right to sell tickets.
"The club is not to blame for what happened against Eintracht, but it is responsible," Laporta said in a news conference on Tuesday which was called to explain what went wrong.
"We didn't sell tickets to German fans beyond the 5,000 away tickets. Sales from Germany weren't allowed and there were many people trying to buy tickets from there. The system of control worked up to a point, but some organised groups were able to breach the mechanisms in place.
"We inherited the system from the previous board. We thought it could work but we have seen that for special games it doesn't.
"Tickets will now be non-transferrable for non-domestic matches and high-risk games. We are working on other measures so that it does not happen again."
The presence of so many away fans in Camp Nou led to fan protests before Monday's surprise LaLiga defeat to Cadiz.
Around 100 fans chanted for Laporta to resign outside the stadium before kick-off, while the supporters' group that fills the section behind one of the goals opted to boycott the game.
However, Laporta remains adamant that members carry more blame for what happened than the club.
"A group of members misused their season tickets, which they ceded to German fans," he continued. "It is sad because we love this club and it is hard to imagine season ticket holders giving their tickets to rival fans. But this happened and it will be subject to analysis.
"There are around 7,000 members that purchased tickets with the discount code and [those tickets] ended up in German hands. We don't want it to become a witch hunt, but there is a lot of disappointment and will look into possibly taking action.
"We have also detected malpractice from a tour operator, whose contract with the club has now been terminated."
Laporta did concede the club did also need to self-reflect on the events, but said turning Frankfurt supporters away on the day would have led to bigger problems.
"I am sure we could have done better," he said. "It concerned us to see so many German fans arriving at the ground, but if we impeded them from entering, we would be talking about more serious incidents."