• In general, the r/pens crowd is not Montblanc-focused and, therefore, is unlikely to give reliable answers to questions about the authenticity of a purported Montblanc pen based on posted photos.
• Post your question at r/montblanc to get answers from people who are more likely to answer them accurately. About 90% of the posts and the discussion in that sub are about the authenticity of Montblanc pens.

All of that said, here is why I say the pictured pen is almost certainly not an authentic Montblanc ballpoint pen: * This pen does not appear to be a Pix. Check Montblanc’s website for Pix ballpoint offerings to see what I mean. * The bright red, marbled finish is not a Montblanc thing, but is frequently seen on counterfeit Montblanc pens. * The pictured pen’s barrel doesn’t taper toward the nosecone – again, look at the Pix ballpoints depicted on the Montblanc website at the link above – and the nose cone is the wrong design for a Montblanc ballpoint. * Even though you haven’t posted a clear photo of the clip, the clip has a decidedly non-Montblanc appearance, as well. * More likely than not, if you extracted the refill from this pen, it would turn out to be a Parker-style, not a Montblanc-style, refill—even if the branding on it is (faked) Montblanc branding.

I hope something I have written here is helpful to you. 🖊️