Except as otherwise provided by this article, “sale” or “sell” means every disposition, or attempt or arrangement to dispose, of a security or interest in a security for value, whether done by direct or indirect means. A security is conclusively presumed to be sold for value if given with any purchase of any nature or if given as a bonus on account of a purchase. “Sale” or “sell” shall also mean a contract of sale, an exchange, any change in the rights, preferences, privileges or restrictions on outstanding securities, an attempt to sell, an option of sale, a solicitation of a sale, a subscription or an offer to sell directly or by an agent, or a circular letter, advertisement or otherwise.