# EDGAR Filing Document

**Accession Number:** 0001657677
**File Stem:** 0001193125-26-264426
**Filing Date:** 2026-6
**Character Count:** 17922
**Document Hash:** bd2674b7fe38fb1a35b5d9b98d39ace2
**Contains OCR:** False
**Source Format:** 

## Filing Content

## Filing Summary
**0001193125-26-264426.hdr.sgml**: 20260609

**ACCESSION NUMBER**: 0001193125-26-264426

**CONFORMED SUBMISSION TYPE**: S-1MEF

**PUBLIC DOCUMENT COUNT**: 13

**FILED AS OF DATE**: 20260609

**DATE AS OF CHANGE**: 20260609

**EFFECTIVENESS DATE**: 20260609

**FILER**: 

**COMPANY DATA:**
- **COMPANY CONFORMED NAME:** Parabilis Medicines, Inc.
- **CENTRAL INDEX KEY:** 0001657677
- **STANDARD INDUSTRIAL CLASSIFICATION:** PHARMACEUTICAL PREPARATIONS [2834]
- **ORGANIZATION NAME:** 03 Life Sciences
- **EIN:** 474505725
- **STATE OF INCORPORATION:** DE
- **FISCAL YEAR END:** 1231

**FILING VALUES:**
- **FORM TYPE:** S-1MEF
- **SEC ACT:** 1933 Act
- **SEC FILE NUMBER:** 333-296655
- **FILM NUMBER:** 261077513

**BUSINESS ADDRESS:**
- **STREET 1:** 30 ACORN PARK DRIVE
- **STREET 2:** 6TH FLOOR
- **CITY:** CAMBRIDGE
- **STATE:** MA
- **ZIP:** 02140
- **BUSINESS PHONE:** 617-945-9510

**MAIL ADDRESS:**
- **STREET 1:** 30 ACORN PARK DRIVE
- **STREET 2:** 6TH FLOOR
- **CITY:** CAMBRIDGE
- **STATE:** MA
- **ZIP:** 02140

**FORMER COMPANY:**
- **FORMER CONFORMED NAME:** FOG PHARMACEUTICALS, INC.
- **DATE OF NAME CHANGE:** 20151105

**As filed with the Securities and Exchange Commission on June 9, 2026.** 

**Registration No. 333–** 

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**UNITED STATES** 

**SECURITIES AND EXCHANGE COMMISSION** 

**Washington, D.C. 20549** 

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**FORM S-1** 

**REGISTRATION STATEMENT** 

***UNDER*** 

***THE SECURITIES ACT OF 1933*** 

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**Parabilis Medicines, Inc.** 

**(Exact name of registrant as specified in its charter)** 

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| | | |
|:---|:---|:---|
| **Delaware** | **2834** | **47-4505725** |
| **(State or other jurisdiction of**<br>**incorporation or organization)** | **(Primary Standard Industrial**<br>**Classification Code Number)** | **(I.R.S. Employer**<br>**Identification No.)** |

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**30 Acorn Park Drive**

**Cambridge, MA 02140** 

**(617) 945-9510**

**(Address, including zip code, and telephone number, including area code, of registrant's principal executive offices)** 

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**Mathai Mammen, M.D., Ph.D.** 

**Chief Executive Officer** 

**30 Acorn Park Drive** 

**Cambridge, MA 02140** 

**(617) 945-9510**

**(Name, address, including zip code, and telephone number, including area code, of agent for service)** 

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***Copies to:*** 

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| | | |
|:---|:---|:---|
| **Kingsley L. Taft**<br>**Gregg L. Katz**<br>**Alicia M. Tschirhart**<br>**Goodwin Procter LLP**<br>**100 Northern Avenue**<br>**Boston, MA 02210**<br>**(617) 570-1000** | **Teresa Jurgensen**<br>**General Counsel**<br>**Parabilis Medicines, Inc.**<br>**30 Acorn Park Drive**<br>**Cambridge, MA 02140**<br>**(617) 945-9510** | **Brian K. Rosenzweig**<br>**Alicia Zhang**<br>**Charles A. Dobb**<br>**Covington & Burling LLP**<br>**30 Hudson Yards**<br>**New York, NY 10001**<br>**(212) 841-1000** |

---

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**Approximate date of commencement of proposed sale to the public**: As soon as practicable after the effective date of this registration statement.

If any of the securities being registered on this Form are to be offered on a delayed or continuous basis pursuant to Rule 415 under the Securities Act of 1933, check the following box. ☐

If this Form is filed to register additional securities for an offering pursuant to Rule 462(b) under the Securities Act, please check the following box and list the Securities Act registration statement number of the earlier effective registration statement for the same offering. ☒ **333-296032**

If this Form is a post-effective amendment filed pursuant to Rule 462(c) under the Securities Act, check the following box and list the Securities Act registration statement number of the earlier effective registration statement for the same offering. ☐

If this Form is a post-effective amendment filed pursuant to Rule 462(d) under the Securities Act, check the following box and list the Securities Act registration statement number of the earlier effective registration statement for the same offering. ☐

Indicate by check mark whether the registrant is a large accelerated filer, an accelerated filer, a non-accelerated filer, a smaller reporting company or an emerging growth company. See the definitions of "large accelerated filer," "accelerated filer," "smaller reporting company" and "emerging growth company" in Rule 12b-2 of the Exchange Act.

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| | | | |
|:---|:---|:---|:---|
| Large accelerated filer | ☐ | Accelerated filer | ☐ |
| Non-accelerated filer | ☒ | Smaller reporting company | ☒ |
|  |  | Emerging growth company | ☒ |

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If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 7(a)(2)(B) of the Securities Act. ☐

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**The Registration Statement shall become effective upon filing in accordance with Rule 462(b) promulgated under the Securities Act of 1933, as amended.** 

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**EXPLANATORY NOTE AND INCORPORATION BY REFERENCE** 

This Registration Statement is being filed pursuant to Rule 462(b) under the Securities Act of 1933, as amended (the "Securities Act"), for the sole purpose of increasing the aggregate number of shares of common stock offered by Parabilis Medicines, Inc. (the "Registrant") by 191,666 shares, 25,000 of which are subject to purchase upon exercise of the underwriters' option to purchase additional shares of the Registrant's common stock. The contents of the Registration Statement on Form S-1, as amended (File No. 333-296032), filed by the Registrant with the Securities and Exchange Commission (the "Commission") pursuant to the Securities Act, which was declared effective by the Commission on June 9, 2026, including all exhibits thereto, are incorporated by reference into this Registration Statement. The additional shares of common stock that are being registered for issuance and sale pursuant to this Registration Statement are in an amount and at a price that together represents no more than 20% of the maximum aggregate offering price set forth in the filing fee table filed as Exhibit 107 to the Registration Statement.

The required opinion and consents are listed on an Exhibit Index attached hereto and filed herewith.

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**EXHIBIT INDEX** 

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| | |
|:---|:---|
| **Exhibit**<br>**No.** | **Exhibit Index** |
| 5.1 | [<u>Opinion of Goodwin Procter LLP.</u>](ck0001657677-ex5_1.htm) |
| 23.1 | [<u>Consent of PricewaterhouseCoopers LLP, independent registered public accounting firm.</u>](ck0001657677-ex23_1.htm) |
| 23.2 | [<u>Consent of Goodwin Procter LLP (included in Exhibit 5.1)</u>](ck0001657677-ex5_1.htm) |
| 24.1\* | [<u>Power of Attorney (included on signature page).</u>](https://www.sec.gov/Archives/edgar/data/1657677/000119312526230994/ck0001657677-20260519.htm#power_of_attorney_and_signatures) |
| 107 | [<u>Filing Fee Table</u>](ck0001657677-exfiling_fees.htm) |

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\* Previously filed on the signature page to the Registrant's Registration Statement on Form S-1, as amended (File No. 333-296032), originally filed with the Securities and Exchange Commission on May 19, 2026 and incorporated by reference herein.

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**SIGNATURES** 

Pursuant to the requirements of the Securities Act of 1933, as amended, the registrant has duly caused this registration statement on Form S-1 to be signed on its behalf by the undersigned, thereunto duly authorized, in the City of Cambridge, Massachusetts, on the 9th day of June, 2026.

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| | |
|:---|:---|
| **PARABILIS MEDICINES, INC.** | **PARABILIS MEDICINES, INC.** |
| By: | /s/ Mathai Mammen |
| Name: | Mathai Mammen, M.D., Ph.D. |
| Title: | Chairman, Chief Executive Officer and President |

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Pursuant to the requirements of the Securities Act of 1933, as amended, this Registration Statement on Form S-1 has been signed by the following person in the capacities and on the date indicated.

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| | | |
|:---|:---|:---|
| **Signature** | **Title** | **Date** |
| /s/Mathai Mammen | Chairman, Chief Executive Officer and President<br>(*Principal Executive Officer*) | June 9, 2026 |
| Mathai Mammen, M.D., Ph.D. | Chairman, Chief Executive Officer and President<br>(*Principal Executive Officer*) | June 9, 2026 |
| /s/Thomas Kotarakos | Chief Financial Officer (*Principal Financial Officer and Principal Accounting Officer*) | June 9, 2026 |
| Thomas Kotarakos | Chief Financial Officer (*Principal Financial Officer and Principal Accounting Officer*) | June 9, 2026 |
| \* | Director | June 9, 2026 |
| Alexis Borisy | Director | June 9, 2026 |
| \* | Director | June 9, 2026 |
| Edward Fitzgerald | Director | June 9, 2026 |
| \* | Director | June 9, 2026 |
| Rick Klausner, M.D. | Director | June 9, 2026 |
| \* | Director | June 9, 2026 |
| Alan Sebulsky  | Director | June 9, 2026 |
| \* | Director | June 9, 2026 |
| Jake Simson, Ph.D. | Director | June 9, 2026 |
| \* | Director | June 9, 2026 |
| Barbara Weber, M.D. | Director | June 9, 2026 |
| \* | Director | June 9, 2026 |
| Krishna Yeshwant, M.D. | Director | June 9, 2026 |

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| | |
|:---|:---|
| \* By: | /s/ Mathai Mammen |
|  | Mathai Mammen |
|  | Attorney-in-Fact |

---

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## Exhibit 5.1

**Exhibit 5.1**

June 9, 2026

Parabilis Medicines, Inc.

30 Acorn Park Drive

Cambridge, MA 02140

Re: <u>Securities Registered under Registration Statement on Form S-1</u>

We have acted as counsel to you in connection with your filing of (i) a Registration Statement on Form S-1 (File No. 333-296032) (as amended or supplemented, the "Initial Registration Statement") pursuant to the Securities Act of 1933, as amended (the "Securities Act") and (ii) a second Registration Statement on Form S-1 filed pursuant to Rule 462(b) promulgated under the Securities Act (the "462(b) Registration Statement," and together with the Initial Registration Statement, the "Registration Statement"). This opinion letter is being furnished to you in connection with your filing of the 462(b) Registration Statement relating to the registration of the offering by Parabilis Medicines, Inc., a Delaware corporation (the "Company"), of up to 191,666 shares (the "Shares") of the Company's Common Stock, $0.0001 par value per share, including Shares purchasable by the underwriters upon their exercise of an over-allotment option granted to the underwriters by the Company. The Shares are being sold to the several underwriters named in, and pursuant to, an underwriting agreement among the Company and such underwriters (the "Underwriting Agreement").

We have reviewed such documents and made such examination of law as we have deemed appropriate to give the opinions set forth below. We have relied, without independent verification, on certificates of public officials and, as to matters of fact material to the opinions set forth below, on certificates of officers of the Company.

The opinion set forth below is limited to the Delaware General Corporation Law.

Based on the foregoing, we are of the opinion that the Shares have been duly authorized and, when delivered and paid for in accordance with the terms of the Underwriting Agreement, will be validly issued, fully paid and non-assessable.

This opinion letter and the opinion it contains shall be interpreted in accordance with the Core Opinion Principles as published in 74 *Business Lawyer* 815 (Summer 2019).

We hereby consent to the inclusion of this opinion as Exhibit 5.1 to the 462(b) Registration Statement and to the references to our firm under the caption "Legal Matters" in the Registration Statement. In giving our consent, we do not admit that we are in the category of persons whose consent is required under Section 7 of the Securities Act or the rules and regulations thereunder.

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| |
|:---|
| Very truly yours, |
| /s/ Goodwin Procter LLP |
| GOODWIN PROCTER LLP |

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## Exhibit 23.1

**Exhibit 23.1**

CONSENT OF INDEPENDENT REGISTERED PUBLIC ACCOUNTING FIRM

We hereby consent to the incorporation by reference in this Registration Statement on Form S-1 of our report dated April 2, 2026, except for the effects of the reverse stock split discussed in Note 18 to the consolidated financial statements, as to which the date is June 4, 2026, relating to the financial statements, which appears in Amendment No. 3 to the Registration Statement on Form S-1 (No. 333- 296032) of Parabilis Medicines, Inc. We also consent to the reference to us under the heading "Experts" in Amendment No. 3 to the Registration Statement on Form S-1 (No. 333-296032) incorporated by reference in this Registration Statement.

/s/ PricewaterhouseCoopers LLP

Boston, Massachusetts

June 9, 2026

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## Ex-Filing

?xml version='1.0' encoding='ASCII'? EX-FILING FEES

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| |
|:---|
| &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; **Calculation of Filing Fee Tables**  |
| &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; **S-1**  |
| &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; **Parabilis Medicines, Inc.**  |

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| | | | | | | | | | |
|:---|:---|:---|:---|:---|:---|:---|:---|:---|:---|
| | | &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; **Security Type**  | &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; **Security Class Title**  | &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; **Fee Calculation or Carry Forward Rule**  | &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; **Amount Registered**  | &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; **Proposed Maximum Offering Price Per Unit**  | &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; **Maximum Aggregate Offering Price**  | &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; **Fee Rate**  | &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; **Amount of Registration Fee**  |
| **Newly Registered Securities** | **Newly Registered Securities** | **Newly Registered Securities** | **Newly Registered Securities** | **Newly Registered Securities** | **Newly Registered Securities** | **Newly Registered Securities** | **Newly Registered Securities** | **Newly Registered Securities** | **Newly Registered Securities** |
| Fees to be Paid | 1 | Equity | Common Stock, par value $0.0001 per share | 457(a) | 191666 | $20.00 | $3833320.00 | 0.0001381 | $529.38 |
| Fees Previously Paid |  |  |  |  |  |  |  |  |  |
| **Carry Forward Securities** | **Carry Forward Securities** | **Carry Forward Securities** | **Carry Forward Securities** | **Carry Forward Securities** | **Carry Forward Securities** | **Carry Forward Securities** | **Carry Forward Securities** | **Carry Forward Securities** | **Carry Forward Securities** |
| Carry Forward Securities |  |  |  |  |  |  |  |  |  |
|  |  |  | Total Offering Amounts: | Total Offering Amounts: | Total Offering Amounts: |  | $3833320.00  |  | $529.38  |
|  |  |  | Total Fees Previously Paid:  | Total Fees Previously Paid:  | Total Fees Previously Paid:  |  |  |  | $0.00  |
|  |  |  | Total Fee Offsets:  | Total Fee Offsets:  | Total Fee Offsets:  |  |  |  | $0.00  |
|  |  |  | Net Fee Due:  | Net Fee Due:  | Net Fee Due:  |  |  |  | $529.38  |

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&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; **Offering Note** <br>

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; <sup>1</sup> (1) Represents only the additional number of shares being registered and includes 25,000 shares of common stock that the underwriters have the option to purchase. Does not include the securities that the Registrant previously registered on the Registration Statement on Form S-1 (File No. 333-296032), as amended (the "Prior Registration Statement"). (2) Estimated solely for the purpose of computing the registration fee in accordance with Rule 457(a) under the Securities Act of 1933, as amended (the "Securities Act").

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| |
|:---|
| |
| **Rules 457(b) and 0-11(a)(2)** |
| Fee Offset Claims |
| Fee Offset Sources |
| **Rule 457(p)** |
| Fee Offset Claims |
| Fee Offset Sources |

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