If the filing person has previously filed a statement on Schedule 13G to report the acquisition that is the subject of this Schedule 13D, and is filing this schedule because of §§ 240.13d-1(e), 240.13d-1(f) or 240.13d-1(g), check the following box. Checkbox not checked

The information required on the remainder of this cover page shall not be deemed to be “filed” for the purpose of Section 18 of the Securities Exchange Act of 1934 (“Act”) or otherwise subject to the liabilities of that section of the Act but shall be subject to all other provisions of the Act (however, see the Notes).




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SCHEDULE 13D






SCHEDULE 13D






SCHEDULE 13D






SCHEDULE 13D






SCHEDULE 13D






SCHEDULE 13D






SCHEDULE 13D


 
Simcoe Capital Management, LLC
 
Signature:/s/ Jeffrey Jacobowitz
Name/Title:Jeffrey Jacobowitz, Managing Member
Date:05/19/2026
 
SIMCOE PARTNERS L P
 
Signature:/s/ Jeffrey Jacobowitz
Name/Title:Jeffrey Jacobowitz, Managing Member of Simcoe Management Company, LLC (its General Partner)
Date:05/19/2026
 
Simcoe Select, LP
 
Signature:/s/ Jeffrey Jacobowitz
Name/Title:Jeffrey Jacobowitz, Managing Member of Simcoe Management Company, LLC (its General Partner)
Date:05/19/2026
 
SIMCOE MANAGEMENT COMPANY, LLC
 
Signature:/s/ Jeffrey Jacobowitz
Name/Title:Jeffrey Jacobowitz, Managing Member
Date:05/19/2026
 
SDR Partners, LLC
 
Signature:/s/ Jeffrey Jacobowitz
Name/Title:Jeffrey Jacobowitz, Managing Member of Simcoe Management Company, LLC (its Investment Manager)
Date:05/19/2026
 
Jacobowitz Jeffrey
 
Signature:/s/ Jeffrey Jacobowitz
Name/Title:Jeffrey Jacobowitz
Date:05/19/2026

Exhibit 1

Transactions in the Shares During the Past Sixty Days

Shares of Common Stock

Purchased/(Sold)

Price Per

Share($)

Date of

Purchase/Sale

 

SIMCOE PARTNERS, L.P.

 

14,094 43.0468 05/11/2026
53,057 43.1932 05/12/2026
51,739 42.6869 05/13/2026
67,451 43.1963 05/14/2026
24,807 40.8226 05/15/2026
40,107 41.2995 05/18/2026
55,255 39.0508 05/19/2026

 

SIMCOE SELECT, L.P.

 

18,747 43.1932 05/12/2026
18,282 42.6869 05/13/2026
23,833 43.1963 05/14/2026
8,765 40.8226 05/15/2026
14,173 41.2995 05/18/2026
3,045 39.0508 05/19/2026

 

SDR PARTNERS, LLC

 

906 43.0468 05/11/2026
1,985 43.1932 05/12/2026
1,936 42.6869 05/13/2026
2,524 43.1963 05/14/2026
928 40.8226 05/15/2026
1,501 41.2995 05/18/2026
1,440 39.0508 05/19/2026

 

Exhibit 99.1

JOINT FILING AGREEMENT

 

In accordance with Rule 13d-1(k)(1)(iii) under the Securities Exchange Act of 1934, as amended, the persons named below agree to the joint filing on behalf of each of them of a Statement on Schedule 13D (including additional amendments thereto) with respect to the shares of Common Stock of Koppers Holdings Inc., a Pennsylvania corporation. This Joint Filing Agreement shall be filed as an Exhibit to such Statement.

Simcoe Capital Management, LLC
 
By:

/s/ Jeffrey Jacobowitz

 
  Jeffrey Jacobowitz, Managing Member
Date: 05/19/2026

 

SIMCOE PARTNERS L P
 
By:

/s/ Jeffrey Jacobowitz

 
  Jeffrey Jacobowitz, Managing Member of Simcoe Management Company, LLC (its General Partner)
Date: 05/19/2026

 

Simcoe Select, LP
 
By:

/s/ Jeffrey Jacobowitz

 
  Jeffrey Jacobowitz, Managing Member of Simcoe Management Company, LLC (its General Partner)
Date: 05/19/2026

 

SIMCOE MANAGEMENT COMPANY, LLC
 
By:

/s/ Jeffrey Jacobowitz

 
  Jeffrey Jacobowitz, Managing Member
Date: 05/19/2026

 

SDR Partners, LLC
 
By:

/s/ Jeffrey Jacobowitz

 
  Jeffrey Jacobowitz, Managing Member of Simcoe Management Company, LLC (its Investment Manager)
Date: 05/19/2026

 

Jacobowitz Jeffrey
 
By:

/s/ Jeffrey Jacobowitz

 
  Jeffrey Jacobowitz
Date: 05/19/2026