...July 29, 2019 NEW YORK (S&P Global Ratings) July 29, 2019--S&P Global Ratings today assigned its 'A-' issue-level rating to Union Pacific Corp.'s proposed senior unsecured notes due 2039 and 2059. The company will use the proceeds from these notes for general corporate purposes, including to repurchase its shares. ISSUE RATINGS--SUBORDINATION RISK ANALYSIS Capital structure - Union Pacific's capital structure consists primarily of senior unsecured debt and a modest amount of secured debt, most of which was issued at the parent level. Analytical conclusions - We rate Union Pacific's unsecured debt 'A-', the same level as our issuer credit rating on the company, because no significant elements of subordination risk are present in its capital structure....