Marshal D. Teach aka Blackbeard is one of the if not the most important antagonists of the series. He is a very powerful person too, having the two most powerful Devil Fruits and a formidable amount of strength and endurance. However until now he have never shown any signs of having Haki. Nonetheless, when I thought about it, it seemed to me that it is highly likely that he possesses Haki. Why? There are several reasons. When he met Luffy in Impel Down he commented that Luffy's Haki has gone up, while indicates that he is familiar with the concept of Haki and therefore might have it himself as he is a veteran pirate. Also he is a D. and most of the D.s shown by far ad some haki ability. Luffy has all types of Haki, Ace had King's Haki, Garp has at least the Armament Haki, Saul also had Haki as he was a Vice Admiral. Also it is probable that Dragon has Haki and Roger had Haki. So why not Teach? (I am not counting Rouge as she we know too little about her.) Aside from that, the fact that Blackbeard manged to injure Shanks (who is one of the most prominent Haki users of the series) with out his Devil Fruit powers may imply that he also had has Haki to go on a fight against Shanks. As to why he did not use it, my reasoning is, as he has Yami Yami no Mi now, he does not need Haki to negate Devil Fruit powers. Come to think of it, only a very few people actually uses Haki, until now the only people to use it in battle are, Shanks, Rayleigh, Marco, Jozu, Vista, Whitebeard, Hancock and the Kuja tribe, Enel and his group, Garp, the three Admirals, Sentomaru and Luffy. I mean even though they can the Vice Admirals never used Haki in battle till now, even when they were defeated and he Admirals only used it once when defending the execution plaza against Whitebeard's attack. Which means haki is not widely used, especially by fruit users. Therefore Teach might have refrained from using it, even though he has it. So what do you think?