On Tuesday, coking coal producer SunCoke Energy Partners filed an amended form S-1 (S-1/A) with the SEC, updating the commission and potential investors on the details of its planned initial public offering, first announced in an S-1 filing on Aug. 8.

In its filing, SunCoke describes itself as a company "formed to acquire ... an interest in each of two entities that own our sponsors' [Haverhill and Middletown] cokemaking facilities and related assets, which will result in [our] owning a 65% interest in each of these entities." The entities in question themselves operate a combined 300 cokemaking ovens producing as much as 1.7 million tons of coking coal annually, and currently operating at full capacity. Their primary customers are -- and, consequently, SunCoke's primary customers upon its IPO will be -- Ohio steelmaker AK Steel (AKS) and also ArcelorMittal (MT 0.95%), the world's largest steelmaker.

In its filing, SunCoke noted that it intends to IPO with an initial offering of 13.5 million common units (unlike corporations, which issue common stock to shareholders, limited partnerships such as SunCoke float common "units"), pricing each unit at somewhere between $19 and $21 initially.

Underwriters on the offering include Barclays (BCS 1.19%), Bank of America Merrill Lynch, Citigroup (C 1.41%), Credit Suisse (CS), JPMorgan Chase (JPM 2.51%), Evercore Partners (EVR 0.58%), Goldman Sachs (GS 0.22%), RBC Capital Markets (RY 0.99%), and UBS Investment Bank(UBS -0.21%).

SunCoke intends to go public on the New York Stock Exchange with the ticker symbol SXCP.