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"the campaign has withdrawn its lawsuit against the DNC today but continues to implore the DNC to address the systemic instability that remains in its voter file system," the campaign said

"The Sanders campaign never "exported" any unauthorized voter file data," the campaign added

Washington CNN  — 

Bernie Sanders’ campaign on Friday withdrew its lawsuit against the Democratic National Committee after claiming the party had unfairly blocked its access to a critical voter database in December.

The lawsuit came after a Sanders staffer exploited a software error to improperly access confidential voter information collected by Hillary Clinton’s team. The DNC database is a goldmine of information about voters and being blocked from it threatened to complicate Sanders’ outreach efforts just weeks before the Iowa caucuses. The incident also fueled a long-held belief in the Sanders camp and among his allies that the DNC was stacking the deck in favor of Clinton.

A DNC investigation, the results of which were also released Friday, concluded that the wrongdoing did not go beyond the four Sanders staffers who accessed the database and were fired soon after the incident came to light.

“With the investigation behind us, the campaign has withdrawn its lawsuit against the DNC today but continues to implore the DNC to address the systemic instability that remains in its voter file system,” Sanders’ campaign said in a statement.

The DNC agreed to restore the Sanders campaign’s access to the database by the next day. The campaign agreed to cooperate in an independent investigation of the data breach and to pay a share of those costs.

“An independent investigation of the firewall failures in the DNC’s shared voter file database has definitively confirmed that the original claims by the DNC and the Clinton campaign were wholly inaccurate – the Sanders campaign never ‘stole’ any voter file data,” the campaign said in its statement Friday.

“The Sanders campaign never ‘exported’ any unauthorized voter file data; and the Sanders campaign certainly never had access to the Clinton campaign’s ‘strategic road map,’” the campaign added.

The Sanders team ran multiple searches in Iowa, New Hampshire, Nevada, South Carolina and about 10 March states, including Florida and Colorado, after it noticed the error. One of the data sets it accessed was a Clinton spreadsheet that ranked voters’ enthusiasm – a potential opportunity for Sanders’ campaign to target voters who were hesitant to support the former secretary of state.

Sanders apologized for the breach during a Democratic debate in December. The Clinton campaign declined to comment on the record Friday.

Friday’s developments come as Sanders badly trails Clinton in the Democratic primary fight. Earlier in the week, Sanders himself acknowledged that he has a “narrow path” to the nomination, and Oregon Sen. Jeff Merkley, Sanders’ lone supporter in the Senate, told CNN Thursday that if the Vermont senator is still losing to Clinton after the primary season concludes in June, he should end his campaign rather than take his bid to the party convention.

CNN’s Dan Merica contributed to this report.