EXECUTION COPY REGISTRATION RIGHTS AGREEMENT

Exhibit 4.1

EXECUTION COPY

REGISTRATION RIGHTS AGREEMENT

SEACOR HOLDINGS INC.

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Dated as of March 16, 2005

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REGISTRATION RIGHTS AGREEMENT

This REGISTRATION RIGHTS AGREEMENT (this "Agreement"), dated as of

March 16, 2005, is entered into by and among SEACOR HOLDINGS INC., a Delaware

corporation (including its successors, the "Company"), and the persons (each a

"Holder" and collectively, the "Holders") listed on the signature pages hereof.

RECITALS

WHEREAS, the Company, SBLK Acquisition Corp., a Delaware corporation,

CORBULK LLC, a Delaware limited liability company and Seabulk International,

Inc., a Delaware corporation, are parties to an Agreement and Plan of Merger,

dated as of the date hereof (the "Merger Agreement"); and

WHEREAS, pursuant to the Merger Agreement, the Holders will receive

shares of common stock, par value $0.01 per share (the "Common Stock"), of the

Company.

NOW, THEREFORE, in consideration of the promises, mutual covenants

and agreements hereinafter contained and for other good and valuable

consideration, the receipt and sufficiency of which are hereby acknowledged, the

parties hereto agree as follows:

ARTICLE 1

EFFECTIVENESS; DEFINITIONS

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1.1 Effectiveness. This agreement shall be of no force or effect

prior to the "Effective Time" as defined in the Merger Agreement (hereinafter,

the "Effective Time") and shall, except as otherwise provided herein, be of full

force and effect from and after the Effective Time. In the event that the Merger

Agreement is terminated for any reason prior to the Effective Time, this

Agreement shall terminate.

1.2 Definitions.

"Advice" shall have the meaning set forth in Section 2.4.3 hereof.

"Affiliate" means, with respect to any Person, any Person who,

directly or indirectly, controls, is controlled by or is under common control

with any Person.

"Agreement" shall have the meaning set forth in the introductory

paragraph hereof.

"Broker-Dealer" means a broker or dealer registered with the SEC as

such under the Exchange Act or a "bank" as defined by the Exchange Act.

"Business Day" means a day other than a Saturday, Sunday or other day

on which commercial banks are authorized or required to close under the laws of

the United States or the State of New York.

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"Common Stock" shall have the meaning set forth in the Recitals

hereof.

"Common Stock Equivalents" means, without duplication with any other

Common Stock or Common Stock Equivalents, any rights, warrants, options,

convertible securities or indebtedness, exchangeable securities or indebtedness,

or other rights, exercisable for or convertible or exchangeable into, directly

or indirectly, Common Stock of the Company and securities convertible or

exchangeable into Common Stock of the Company, whether at the time of issuance

or upon the passage of time or the occurrence of such future event.

"Company" shall have the meaning set forth in the introductory

paragraph hereof.

"Company Notice" shall have the meaning set forth in Section 2.3.1

hereof.

"Deferral Period" shall have the meaning set forth in Section 2.6

hereof.

"Effective Time" shall have the meaning set forth in Section 1.1

hereof.

"Exchange Act" means the Securities Exchange Act of 1934, as amended,

or any similar federal statute, and the rules and regulations promulgated by the

SEC thereunder.

"Holder" and "Holders" shall have the meaning set forth in the

introductory paragraph of this Agreement and shall include any Affiliate of any

such Holder to whom Registrable Securities are transferred by such Holder.

"NASD" means the National Association of Securities Dealers, Inc.

"Nautilus" means Nautilus Acquisition, L.P. and any of its

Affiliates.

"Notifying Holder" shall have the meaning set forth in Section 2.2.1

hereof.

"Person" or "person" means any individual, corporation, partnership,

limited liability company, joint venture, association, joint-stock company,

trust, unincorporated organization or government or other agency or political

subdivision thereof.

"Piggyback Notice" shall have the meaning set forth in Section 2.2.1.

"Receiving Holders" shall have the meaning set forth in Section 2.2.1

hereof.

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"register," "registered" and "registration" refer to a registration

effected by preparing and filing a registration statement in compliance with the

Securities Act, and the declaration or ordering of the effectiveness of such

registration statement.

"Registrable Securities" means the shares of Common Stock of the

Company to be acquired by the Holders pursuant to the transactions contemplated

by the Merger Agreement; provided, however, that Registrable Securities shall

not include any such shares sold or otherwise transferred by a Holder except in

the event of a transfer by a Holder to one or more of such Holder's Affiliates.

"Registration Expenses" means all expenses incident to registration

of the Registrable Securities hereunder, including, without limitation, (a) all

SEC and any NASD registration and filing fees and expenses, (b) all fees and

expenses in connection with the registration or qualification of the Registrable

Securities for offering and sale under the securities or "Blue Sky" laws of any

state or other jurisdiction of the United States of America and, in the case of

an underwritten offering, determination of their eligibility for investment

under the laws of such jurisdictions as the managing underwriter or underwriters

may designate, including reasonable fees and disbursements (based on customary

hourly rates), if any, of counsel for the underwriters in connection with such

registrations or qualifications and determination, (c) all expenses relating to

the preparation, printing, distribution and reproduction of the registration

statement required to be filed hereunder, each prospectus included therein or

prepared for distribution pursuant hereto, each amendment or supplement to the

foregoing, the expenses of preparing the Registrable Securities in a form for

delivery for purchase pursuant to such registration or qualification and the

expenses of printing or producing any underwriting agreement(s) and agreement(s)

among underwriters and any "Blue Sky" or legal investment memoranda, any selling

agreements and all other documents to be used in connection with the offering,

sale or delivery of Registrable Securities, (d) messenger, telephone and

delivery expenses of the Company and out-of-pocket travel expenses incurred by

or for the Company's personnel for travel undertaken for any "road show" made in

connection with the offering of securities registered thereby, (e) fees and

expenses of any transfer agent and registrar with respect to the delivery of any

Registrable Securities and any escrow agent or custodian involved in the

offering, (f) fees, disbursements and expenses of counsel and independent

certified public accountants of the Company incurred in connection with the

registration, qualification and offering of the Registrable Securities

(including the expenses of any opinions or "cold comfort" letters required by or

incident to such performance and compliance), (g) fees, expenses and

disbursements of any other persons retained by the Company, including special

experts retained by the Company in connection with such registration, (h)

Securities Act liability insurance (if the Company elects to obtain such

insurance) and (i) the fees and expenses incurred in connection with the

quotation or listing of shares of Registrable Securities on any securities

exchange or automated securities quotation system. Any commissions, fees,

discounts or, except as specified in the immediately preceding sentence,

expenses of any underwriter or Holder incurred in connection with an

underwritten offering of securities registered in accordance with this Agreement

shall not be considered "Registration Expenses."

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"Required Holders" means Holders who, in the aggregate, then own more

than 50% of the Registrable Securities, and who, severally, each then own (i) in

the case of Nautilus, more than 50% of the Registrable Securities owned by

Nautilus and (ii) in the case of Riverstone, more than 50% of the Registrable

Securities owned by Riverstone.

"Riverstone" means each of C/R Marine Domestic Partnership, L.P., C/R

Marine Non-U.S. Partnership, L.P., C/R Marine Coinvestment, L.P. or C/R Marine

Coinvestment II, L.P. and any of their Affiliates.

"Regulation M" means Regulation M under the Securities Act and the

Exchange Act as in effect on the date hereof and such rule as from time to time

amended and any successor rule or regulation under the Securities Act or

Exchange Act.

"Rule 144" means Rule 144 under the Securities Act as in effect on

the date hereof and such rule as from time to time amended and any successor

rule or regulation under the Securities Act.

"Rule 145" means Rule 145 under the Securities Act as in effect on

the date hereof and such rule as from time to time amended and any successor

rule or regulation under the Securities Act.

"Rule 415" means Rule 415 under the Securities Act as in effect on

the date hereof and such rule as from time to time amended and nay successor

rule or regulation under the Securities Act.

"SEC" means the Securities and Exchange Commission or any other

federal agency at the time administering the Securities Act.

"Securities Act" means the Securities Act of 1933, as amended, or any

similar federal statute, and the rules and regulations promulgated by the SEC

thereunder.

"Seller Affiliates" shall have the meaning set forth in Section 2.5.1

hereof.

"Shelf Registration Statement" shall have the meaning provided in

Section 2.1.1 hereof.

"Suspension Notice" shall have the meaning set forth in Section 2.4.3

hereof.

"Underwriting Notice" shall have the meaning set forth in Section

2.2.1 hereof.

1.3 Rules of Construction. Unless the context otherwise requires

(1) a term has the meaning assigned to it;

(2) "or" is not exclusive;

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(3) words in the singular include the plural, and words in the

plural include the singular;

(4) provisions apply to successive events and transactions; and

(5) "herein," "hereof" and other words of similar import refer

to this Agreement as a whole and not to any particular

Article, Section or other subdivision.

ARTICLE 2

REGISTRATION

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2.1 Shelf Registration.

2.1.1 Shelf Registration Statement. The Company shall as promptly as

practicable (but in no event more than 30 days after the Closing Date (as

defined in the Merger Agreement)) prepare and file with the SEC and, thereafter,

use its reasonable best efforts to have declared effective as promptly as

reasonably practicable a registration statement (the "Shelf Registration

Statement") in accordance with Section 2.4.1 hereof relating to the offer and

sale by the Holders at any time and from time to time on a delayed or continuous

basis in accordance with Rule 415, through such method or methods of

distribution as the Holders shall select, and in accordance with this Agreement,

of all the Registrable Securities, and, subject to Section 2.6 hereof, the

Company shall use reasonable best efforts to keep the Shelf Registration

Statement effective under the Securities Act until the third anniversary of the

Effective Time (or for such longer period if extended pursuant to Section 2.6

hereof). In the event the Shelf Registration Statement cannot be kept effective

for such period, the Company shall, subject to Section 2.6 hereof, use

reasonable best efforts to prepare and file with the SEC and have declared

effective as promptly as practicable another registration statement on the same

terms and conditions as the initial Shelf Registration Statement and such

registration statement shall be considered the Shelf Registration Statement for

purposes hereof. The Company shall supplement and amend the Shelf Registration

Statement to reflect changes in the manner of distribution reasonably requested

by the Holders.

2.1.2 Adjustment. If at any time the outstanding shares of

Registrable Securities as a class shall have been increased, decreased, changed

into or exchanged for a different number or class of shares or securities as a

result of a reorganization, recapitalization, reclassification, stock dividend,

stock split, reverse stock split, combination or exchange of shares or other

similar change in capitalization, then an appropriate and proportionate

adjustment shall be made to the number of shares of such stock to be registered

on the Shelf Registration Statement pursuant to Section 2.1.1 hereof.

2.1.3 Expenses. The Company will pay all of the Registration Expenses

in connection with any registration pursuant to this Section 2.1; provided,

however, that in any underwritten offering or other trade by the Holders

effectuated pursuant to this Section 2.1, the Holders shall pay any underwriting

commissions and discounts and fees and expenses of counsel to such Holders.

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2.1.4 Notice of Intended Use of Prospectus. If, at any time on or

after the first anniversary of the Effective Time, any Holder intends to use or

deliver the prospectus forming a part of the Shelf Registration Statement (or

any prospectus supplement or amendment thereto) in connection with any offer or

sale of Registrable Securities covered thereby, such Holder shall first give

written notice thereof to the Company at least two (2) Business Days prior to

the first date such prospectus or prospectus supplement will be used or

delivered by such Holder in connection with such offer or sale. If applicable,

by the close of business on the Business Day following its receipt of such

notice, the Company shall provide a Suspension Notice to any Holder delivering a

notice pursuant this Section 2.1.4 of any suspension of registration rights

pursuant to Section 2.6 hereof.

2.2 Certain Underwritten Offerings Pursuant to the Shelf Registration

Statement.

2.2.1 Underwriting Notice. In the event that the Holders of 50% or

more of the Registrable Securities outstanding at such time (and, with respect

to Riverstone, as otherwise permitted by the last sentence of this Section

2.2.1) shall seek to undertake an underwritten offering of any Registrable

Securities pursuant to the Shelf Registration Statement, such Holders shall

first give written notice thereof (the "Underwriting Notice", and each such

party giving notice, a "Notifying Holder") to the other Holders (the "Receiving

Holders") and the Company at least ten (10) Business Days prior to the

anticipated initiation of such underwritten offering, specifying the number of

Registrable Securities sought to be offered. The Company shall advise the

Notifying Holders and the Receiving Holders and each Receiving Holder shall

advise the Notifying Holders and the Company in writing within five (5) Business

Days after receipt of such Underwriting Notice (or if the Notifying Holders

intend to execute the underwriting agreement with respect to such underwritten

offering prior to such date, the Notifying Holders shall so notify the Company

and the Receiving Holders in the Underwriting Notice, and the Company and each

Receiving Holder shall advise the Notifying Holder in writing on or before the

date on which the underwriting agreement is executed but no less than five (5)

Business Days after receipt of such Underwriting Notice), specifying the number,

if any, of shares of Common Stock of the Company or Registrable Securities the

Company and such Receiving Holders, as applicable, seek to include in such

underwritten offering (each a "Piggyback Notice"), and subject to the next

sentence, such shares of Common Stock of the Company and Registrable Securities

shall be included in such underwritten offering. If the managing underwriter

shall advise the Company and Holders in writing that, in its opinion, the number

of securities requested to be included in such underwritten offering exceeds the

number which can be sold in such offering without adversely affecting the

offering, including with respect to price, the Company and Holders will include

in such underwritten offering, to the extent of the number which the Holders are

so advised can be sold in such offering, (i) first, a pro rata amount, based

upon the number of Registrable Securities sought to be offered by each Holder as

set forth in the Underwriting Notice and the Piggyback Notice, (ii) second,

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securities of the Company sought to be offered by the Company as set forth in

the Piggyback Notice and (iii) third, securities of the Company held by other

Persons having registration rights existing as of the date of this Agreement or

granted in accordance with Section 2.3.5 hereof proposed to be included in such

registration by the holders thereof. Notwithstanding anything contained herein

to the contrary, and whether or not Riverstone owns 50% or more of the

Registrable Securities outstanding at such time, Riverstone shall be entitled to

be the Notifying Holder for at least one of the three underwritten offerings

permitted herein, so long as Riverstone holds greater than the minimum amount

specified in Section 2.2.2(D) hereof.

2.2.2 Procedures. Subject to Section 2.6 hereof, the Company shall

(i) make reasonably available for inspection by the Holders, any underwriter

participating in any disposition pursuant to the Shelf Registration Statement

and any attorney, accountant or other agent retained by the Holders or any such

underwriter, all relevant financial and other records, pertinent corporate

documents and properties of the Company, (ii) cause the Company's officers,

directors, employees, and use its reasonable best efforts to cause the Company's

accountants and auditors, to supply all relevant information reasonably

requested by the Holders or any such underwriter, attorney, accountant or agent

in connection with the underwritten offering, (iii) as may be reasonably

requested, cause the Company's officers and employees to participate in investor

presentations to prospective investors and analysts, including via "road shows,"

and (iv) generally accommodate any participating underwriter's reasonable

requests relating to its due diligence efforts; provided, however, that the

Holders shall only be entitled to effect up to a total of three (3) underwritten

offerings of Registrable Securities pursuant to the Shelf Registration

Statement; provided, further, that no such offering pursuant to Section 2.2.1

shall be made by the Holders:

(A) on more than one occasion during any period of ninety (90)

consecutive days after any other such offering of Registrable Securities in

accordance with this Section 2.2 was consummated;

(B) during the fifteen (15) days prior to the anticipated

consummation of an offering of securities of the same class as the Registrable

Securities and during the sixty (60) days after the consummation of such an

offering, except in the case of an offering registered on Form S-4 or S-8 (or

any successor form) for the registration of securities to be offered in a

transaction of the type referred to in Rule 145 or to be offered to employees of

and/or consultants to the Company or subsidiaries thereof;

(C) within ninety (90) days of the consummation of an offering of

Registrable Securities in which the Holders were offered the opportunity to

participate pursuant to Section 2.3 hereof, provided that all the Registrable

Securities requested by the Holders to be so registered were registered for sale

in such offering; and

(D) unless the Holders will offer for sale at least seven hundred

fifty thousand (750,000) shares of Registrable Securities.

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2.2.3 Effective Registration Statement. For purposes of determining a

Holder's right to sell Registrable Securities pursuant to the Shelf Registration

Statement in an underwritten offering referred to in Section 2.2.1 hereof, an

offering of such nature shall not be deemed to have been effected unless (A) a

registration statement with respect thereto has become effective and remained in

effect for the period set forth in Section 2.4.1(b) hereof (provided, however,

that a registration which does not become effective solely by reason of the

refusal of the Holders to proceed with the offering or the refusal by the

Company to proceed based upon the written opinion of outside counsel to the lead

underwriter delivered to and reasonably acceptable to the Company that so

proceeding is inappropriate as a legal matter for a reason relating to

circumstances of the Holders shall be deemed to have been effected) and (B)

after it has become effective, such registration has not become subject to any

stop order, injunction or other order or requirement of the SEC or other

governmental agency or court for any reason, other than solely by reason of some

act or omission by the Holders with respect thereto, or such stop order,

injunction or other order has been lifted so as to permit such offering and sale

of Registrable Securities and (C) the conditions to closing specified in the

purchase agreement or underwriting agreement entered into in connection with

such registration are satisfied or any failure to satisfy such conditions was

solely by reason of some act or omission by the Holders.

2.2.4 Underwriting Agreements. If requested by the underwriters for

any underwritten offering by the Holders to be conducted pursuant to Section

2.2.1 hereof, the Company will enter into an underwriting agreement with such

underwriters for such offering, such agreement to be in customary form for

offerings of this type and acceptable to the Holders, whose acceptance shall not

be unreasonably withheld, to contain such representations and warranties by the

Company and such other terms as are generally prevailing in agreements of this

type, including, without limitation, representations and indemnities by the

Company and other customary indemnifications. For illustrative purposes, the

representations and warranties and such other terms contained therein and agreed

to by the Company in that certain Registration Rights Agreement, dated as of

December 17, 2004, between the Company and Credit Suisse First Boston LLC, shall

be deemed customary; provided, however, the parties acknowledge and agree that

certain additional representations and warranties and other terms may be added

or changed based on the facts and circumstances at the time of the Company's

entering into the underwriting agreement. The Holders will cooperate with the

Company in the negotiation of the underwriting agreement and will give

consideration to the reasonable suggestions of the Company regarding the form

thereof.

2.2.5 Holdback Agreement. Unless the managing underwriter otherwise

agrees, each of the Company and the Holders agrees (and the Company agrees, in

connection with any underwritten offering effected in accordance with this

Section 2.2, to use its reasonable best efforts to cause its Affiliates to

agree) not to effect any public sale or private offer or distribution of any

Common Stock or Common Stock Equivalents during the period required under

Regulation M prior to the consummation of any underwritten offering in which the

Holders have the opportunity to participate and during such time period after

the consummation of any such underwritten offering of Common Stock (not to

exceed forty-five (45) days) (except, if applicable, as part of such

underwritten offering) as the Company and the managing underwriter may agree.

Any discretionary waiver or termination of the requirements under the foregoing

provisions made by the managing underwriter shall apply to each seller of

Registrable Securities on a pro rata basis in accordance with the number of

Registrable Securities held by each seller.

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2.2.6 Selection of Underwriters. In an underwritten offering of

Registrable Securities effected pursuant to this Section 2.2, the Notifying

Holders shall select the investment banking firm or firms to manage the

underwritten offering; provided, however, that such selection shall be subject

to the consent of the Company, which consent shall not be unreasonably withheld.

2.2.7 Participation in Underwritten Offerings. Neither a Holder nor

any other Person may participate in any underwritten offering in which

Registrable Securities are to be offered pursuant to this Section 2.2 unless

such Person (i) agrees to sell such Person's securities on the basis provided in

any underwriting arrangements approved, subject to the terms and conditions

hereof, by the Company and the Holders to be included in such underwritten

offering and (ii) completes and executes all questionnaires, indemnities,

underwriting agreements and other documents (other than powers of attorney)

reasonably required under the terms of such underwriting arrangements.

2.3 Piggyback Underwritten Offerings.

2.3.1 Right to Piggyback. In the event that the Company shall seek to

undertake an underwritten offering of registered shares of Common Stock of the

Company (whether for the account of the Company or the account of any

securityholder of the Company) on or before the third anniversary of the

Effective Time (or for such longer period if extended pursuant to Section 2.6

hereof), except in the case of an offering registered on Form S-4 or S-8 (or any

successor form) for the registration of securities to be offered in a

transaction of the type referred to in Rule 145 or to be offered to employees of

and/or consultants to the Company or subsidiaries thereof, the Company shall

first give written notice thereof (the "Company Notice") to each Holder of

Registrable Securities, which Company Notice shall be given not less than six

(6) Business Days prior to the anticipated