As noted earlier, Stifel upgraded SBA Communications to Buy from Hold. The firm upgraded the stock on valuation, as it believes that the stock's decline in response to the news of Sprint (S) potentially building its own network has been overdone. In a worst case scenario, Sprrin't initiative would cause the churn rate of SBA's discounted cash flow to increase by 1.8% annually, according to the firm. The company's valuation would be lowered by $9 per share for each 50 basis points of additional churn, putting the stock's worst case valuation at $91 the firm added. Target $112.