“Credit Karma Inc. is in talks to sell its tax-preparation business to Square Inc., according to people familiar with the matter, a move meant to head off potential antitrust objections to the personal-finance portal’s pending $7.1 billion sale to TurboTax maker Intuit Inc. INTU -3.77% Terms of the potential deal couldn’t be learned. A sale of the unit would require approval from the Justice Department, which is concerned that bringing together Credit Karma’s small but growing tax-preparation business with industry-leading TurboTax would leave taxpayers with fewer, and potentially pricier, e-filing options, the people said. Square, the financial-technology company run by Twitter Inc. Chief Executive Jack Dorsey, helps small businesses accept credit- and debit-card payments. Credit Karma’s tax business would augment Square’s Cash App offering , a bank-account alternative that lets consumers transfer money and buy bitcoin from their smartphones.”