A male model, Michael Girgenti, had claimed he was three-year-old Mason's father after meeting Kourtney on a modelling assignment but a DNA test has ruled that out.
In a statement to E! – the channel that airs Keeping Up With The Kardashians - Kourtney said: "While it saddens me to have to address these ridiculous lies — especially when the truth was never in doubt — this story must be put to rest."
Michael had claimed he had sex with Kourtney in 2009 and had wanted joint custody of Mason. When he first made his claims, however, a lawyer for Kourtney dismissed them, accusing Michael of "selling false and fabricated stories" for years.
"His claims are absurd and this is simply another shameful attempt to gain publicity and profit from fictional stories about my client," attorney Todd Wilson told TMZ.
Kourtney and Scott are also parents to one-year-old daughter Penelope.
Neither Kourtney nor Scott has addressed the DNA test or Michael's claims on their social networking sites, so the family seems to be putting it all firmly behind them.
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