SC 13D: Schedule filed to report acquisition of beneficial ownership of 5% or more of a class of equity securities

SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549

SCHEDULE 13D

Under the Securities Exchange Act of 1934

Datum Inc.
(Name of Issuer)

Common Stock
(Title of Class and Securities)

23820810
(CUSIP Number of Class of Securities)

George A. Sissel
General Counsel
Ball Corporation
345 South High Street
Muncie, Indiana 47305
(Name, Address and Telephone Number of Person Authorized
to Receive Notices and Communications)

March 17, 1995
(Date of Event which Requires
Filing of this Statement)

If the filing person has previously filed a statement on
Schedule 13G to report the acquisition which is the
subject of this Statement because of Rule 13d-1(b)(3) or
(4), check the following: ( )

Check the following box if a fee is being paid with this
Statement: (x)


SCHEDULE 13D

CUSIP No. 23820810
_________________________________________________________________
(1) NAMES OF REPORTING PERSONS
S.S. OR I.R.S. IDENTIFICATION NOS. OF ABOVE PERSONS

Ball Corporation
35-0160610
________________________________________________________________
(2) CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP:
(a) ( )
(b) ( )
_________________________________________________________________
(3) SEC USE ONLY

_________________________________________________________________
(4) SOURCE OF FUNDS*
OO
_________________________________________________________________
(5) CHECK BOX IF DISCLOSURE OF LEGAL PROCEEDINGS IS REQUIRED
PURSUANT TO ITEMS 2(d) or 2(e) ( )

__________________________________________________________________
(6) CITIZENSHIP OR PLACE OF ORGANIZATION
Indiana
_________________________________________________________________
(7) SOLE VOTING POWER
NUMBER OF 1,277,778*
SHARES ___________________________________
BENEFICIALLY (8) SHARED VOTING POWER
OWNED BY
EACH ___________________________________
REPORTING (9) SOLE DISPOSITIVE POWER
PERSON 1,277,778*
WITH ___________________________________
(10) SHARED DISPOSITIVE POWER

_________________________________________________________________
(11) AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON
1,277,778*
_________________________________________________________________
(12) CHECK BOX IF THE AGGREGATE AMOUNT IN ROW 11 EXCLUDES CERTAIN
SHARES* ( )

_________________________________________________________________
(13) PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW 11
Approximately 32.3% of the shares outstanding as of March
17, 1995
_________________________________________________________________
(14) TYPE OF REPORTING PERSON*
CO


SCHEDULE 13D

CUSIP No. 23820810
_________________________________________________________________
(1) NAMES OF REPORTING PERSONS
S.S. OR I.R.S. IDENTIFICATION NOS. OF ABOVE PERSONS

Efratom Holding, Inc.
31-1421208
________________________________________________________________
(2) CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP:
(a) ( )
(b) ( )
_________________________________________________________________
(3) SEC USE ONLY

_________________________________________________________________
(4) SOURCE OF FUNDS*
OO
_________________________________________________________________
(5) CHECK BOX IF DISCLOSURE OF LEGAL PROCEEDINGS IS REQUIRED
PURSUANT TO ITEMS 2(d) or 2(e) ( )

__________________________________________________________________
(6) CITIZENSHIP OR PLACE OF ORGANIZATION
Indiana
_________________________________________________________________
(7) SOLE VOTING POWER
NUMBER OF 1,277,778*
SHARES ___________________________________
BENEFICIALLY (8) SHARED VOTING POWER
OWNED BY
EACH ___________________________________
REPORTING (9) SOLE DISPOSITIVE POWER
PERSON 1,277,778*
WITH ___________________________________
(10) SHARED DISPOSITIVE POWER

_________________________________________________________________
(11) AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON
1,277,778*
_________________________________________________________________
(12) CHECK BOX IF THE AGGREGATE AMOUNT IN ROW 11 EXCLUDES CERTAIN
SHARES* ( )

_________________________________________________________________
(13) PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW 11
Approximately 32.3% of the shares outstanding as of March
17, 1995
_________________________________________________________________
(14) TYPE OF REPORTING PERSON*
CO

* On March 17, 1995, Datum Inc. (the "Issuer"), a Delaware corporation,
delivered 1,277,778 newly issued shares (the "Shares") of common stock,
par value $.25 per share, of the Issuer to Efratom Holding, Inc.
("Holding"), a Colorado corporation and a wholly owned subsidiary of Ball
Corporation ("Parent"), an Indiana corporation. As of such date, Parent
and Holding may be deemed to beneficially own the Shares, as indicated in
Rows 11 and 13 of each of the tables above, for purposes of Rule 13d-3
under the Securities and Exchange Act of 1934, as amended.


Item 1. Security and Issuer

This Statement relates to the common stock, par
value $.25 per share (the "Common Stock"), of Datum Inc.,
a Delaware corporation (the "Issuer"), which has its
principal executive offices at 1363 South State College
Blvd., Anaheim, California 92806.

Pursuant to the Stock Purchase Agreement, dated as
of October 20, 1994 (the "Stock Purchase Agreement"), by
and among Ball Corporation, an Indiana corporation ("Par-
ent"), Efratom Holding, Inc., a Colorado corporation and
a wholly owned subsidiary of Parent ("Holding"), and the
Issuer, as part of the consideration for the sale by
Holding to the Issuer of Efratom Time and Frequency
Products, Inc., a Colorado corporation, and Ball Efratom
Elektronik GmbH, a limited liability company organized
under the laws of the Republic of Germany (collectively,
the "Holding Subsidiaries"), the Issuer delivered to
Holding 1,277,778 newly issued shares of Common Stock.
See Item 3 below for more information concerning the
Stock Purchase Agreement.

Item 2. Identity and Background

This Statement is being filed by Parent and Holding,
which have their principal executive offices at 345 South
High Street, Muncie, Indiana 47305 and 10 Longs Peak
Drive, Broomfield, Colorado 80038, respectively.

Holding is a holding company and a wholly owned
subsidiary of Ball.

Ball manufactures metal and glass containers for the
food and beverage industries and provides aerospace
systems and professional services to government and
commercial customers.

Information relating to the directors and executive
officers of Parent and Holding is contained in Appendix A
attached hereto and is incorporated herein by reference.

Neither Parent nor Holding, nor, to the best of
Parent's and Holding's knowledge, any of the persons
listed in Appendix A, has, during the past five years,
been convicted in a criminal proceeding (excluding traf-
fic violations and similar misdemeanors). Neither Parent
nor Holding, nor, to the best of Parent's and Holding's
knowledge, any of the persons listed in Appendix A, has,
during the past five years, been a party to a civil
proceeding of a judicial or administrative body of compe-
tent jurisdiction and as a result of such proceeding was
or is subject to a judgement, decree or final order
enjoining future violations of, or prohibiting or mandat-
ing activities subject to, federal or state securities
laws or finding any violation with respect to such laws.

Item 3. Source and Amount of Funds or Other Consider-
ation

Pursuant to the Stock Purchase Agreement, the Issuer
agreed to purchase from Holding all of the outstanding
shares of common stock of the Holding Subsidiaries for an
aggregate consideration, subject to adjustment, of (i)
$15 million in cash, and (ii) the number of shares (the
"Shares") of the Issuer's Common Stock which equals $11.5
million divided by the average per share closing sale
price (the "Average Closing Price") as reported on the
Nasdaq National Market System for the ten consecutive
trading days ending on the trading day immediately prior
to the date of the special meeting of the Issuer's stock-
holders (the "Special Meeting") for the purpose of ap-
proving the Stock Purchase Agreement and the transactions
contemplated thereby; provided however, that in no event
would such Average Closing Price be less than $7.00 nor
greater than $9.00. The Special Meeting occurred on
March 16, 1995 and the Average Closing Price was $9.00.
The number of Shares that were delivered to Holding by
the Issuer at the closing of the transactions contemplat-
ed by the Stock Purchase Agreement (the "Closing") on
March 17, 1995 was 1,277,778 (representing approximately
32.3% of the shares of Common Stock outstanding immedi-
ately after the issuance of such shares to Holding).

Reference is made to the Stock Purchase Agreement, a
copy of which is included as Exhibit 1 to this Statement
and which is incorporated by reference herein.

Item 4. Purpose of the Transaction

Holding is acquiring beneficial ownership of the
Issuer's Common Stock for investment purposes. Subject
to, among other things, its obligations under the
Stockholder's Agreement described below, Holding may from
time to time seek to increase, reduce or dispose of its
investment in the Common Stock in the open market, in
privately negotiated transactions or otherwise, in which
event such transactions might be through or together with
entities affiliated with Parent or Holding. The determi-
nation to effect any such transaction will depend, among
other things, upon the market price of the Common Stock,
availability of funds, borrowing costs, market condi-
tions, developments affecting the Issuer, Parent and
Holding, other opportunities available to Parent and
Holding and other considerations. Holding intends, from
time to time, to review its investment in the Issuer and
to take such action with respect to the Issuer as it
considers desirable in light of the circumstances then
prevailing.

The Shares are subject to a Stockholder's Agreement
(the "Stockholder's Agreement") entered into by Holding
and the Issuer prior to the Closing. Reference is made
to the Stockholder's Agreement, a copy of which is in-
cluded as Exhibit 2 to this Statement and which is incor-
porated by reference herein.

The Stockholder's Agreement requires the Company to
amend its bylaws to increase the size of its Board of
Directors to eight directors and to appoint two persons
named by Holding, and, at the option of Holding, to
appoint a third person designated by Holding at any time
after the initial appointments (the "Stockholder's
Designees"), to the Company's Board of Directors (allo-
cated equally among the three classes of the Company's
Board of Directors). The number of Stockholder's
Designees shall be adjusted upon any change in the autho-
rized number of directors or changes in the outstanding
Voting Securities (as defined below) of the Company to
correspond to the percentage of such outstanding Voting
Securities represented by the Shares (subject to adjust-
ment for stock splits, stock dividends and other
recapitalizations). The Stockholder's Agreement provides
that the Company will nominate the Stockholder's
Designees for re-election as such persons' terms expire
and will use its best efforts to cause the Stockholder's
Designees to be elected as directors. Holding has ini-
tially appointed R. David Hoover and Donovan B. Hicks to
serve as its designees on the Board of Directors of the
Company and reserves the right to appoint one additional
director.

Pursuant to the Stockholder's Agreement, neither
Holding nor any affiliate of Holding (collectively, the
"Stockholder Group"), will, directly or indirectly,
acquire shares of any class of the Company's capital
stock which is entitled to vote generally in the election
of directors ("Voting Securities"). The foregoing re-
striction will not apply (i) in connection with the
consummation of the transactions contemplated by the
Stock Purchase Agreement, (ii) to stock dividends stock
splits or other like distributions made with respect to
the Shares held by Holding, (iii) during the pendency
pursuant to Section 14(d) of the Securities Exchange Act
of 1934 (the "Exchange Act") of a bona fide, fully fi-
nanced tender offer by any person (other than the Company
or its affiliates or any employee benefit plan of the
Company), if upon the consummation of such tender offer
such person would beneficially own more than 30% of the
Company's Voting Securities, (iv) in the event that any
person (other than Holding or its affiliates, the Company
or any employee benefit plan of the Company) becomes a
beneficial owner of more than 30% of the Company's then
outstanding Voting Securities or proposes to become such
a beneficial owner and such proposal is approved by or
recommended by a majority of the Board of Directors
(excluding the Stockholder's Designees) of the Company,
(v) in the event that the Company has entered into a
definitive merger agreement or a definitive agreement for
the sale of all or substantially all of its assets, or
(vi) to any transaction with the prior approval of a
majority of the Board of Directors (excluding the
Stockholder's Designees). In addition, if any action by
the Company causes the ownership of Voting Securities by
Holding to be less than the percentage ownership of the
outstanding Voting Securities immediately prior to such
action, the foregoing restriction will not apply to any
acquisitions of Voting Securities by Holding to the
extent necessary for Holding to maintain its percentage
ownership of Voting Securities at the level it had imme-
diately prior to such action.

The Stockholder's Agreement prohibits any member of
the Stockholder Group from soliciting proxies or becoming
a "participant" in a "solicitation" (as such terms are
defined in Regulation 14A under the Exchange Act), or
entering into any agreement with any person for the
purpose of voting any Voting Securities, in either case
in opposition to the recommendation of the majority of
the directors of the Company with respect to any election
of directors of the Company; provided that Holding may
vote any shares held by it in opposition to the recommen-
dation of the majority of the directors of the Company on
any matter, including the election of directors.

Subject to certain limitations, with respect to any
Shares that are deemed "Restricted Securities" under the
Securities Act of 1933 (the "Act") (the "Registrable
Securities"), Holding, and/or any transferee of Holding,
who own, in the aggregate, in excess of 250,000 shares of
Registrable Securities may make a written request to the
Company for registration with the Securities and Exchange
Commission (the "Commission"), under and in accordance
with the provisions of the Act, of no less than 250,000
Registrable Securities (a "Demand Registration"). The
Company will serve written notice (the "Notice") of such
registration request to all holders of Registrable Secu-
rities issued by the Company, and subject to such request
the Company will include in such registration all Regis-
trable Securities with respect to which the Company has
received written requests for inclusion therein. The
holders of Registrable Securities shall be entitled to
three Demand Registrations, but no more than one in any
four-month period, the expenses of which, except with
respect to applicable underwriting discounts and commis-
sions, will generally be borne by the Company.

In addition, subject to certain limitations, if the
Company proposes to file a registration statement under
the Act with respect to an offering for its own account
or for the account of others of any class of equity
security, the Company will in each case give written
notice of such proposed filing to holders of Registrable
Securities, at least twenty days before the anticipated
filing date and offer such holders the opportunity to
register such Registrable Securities in such offering, in
accordance with the terms of such offering.

Pursuant to the Stockholder's Agreement, so long as
Holding owns Shares constituting more than 15% of the
outstanding Voting Securities of the Company, the Company
will not, without the consent of Holding, adopt a Share-
holder Rights Plan which would result in the issuance or
separation and exercisability of rights upon the transfer
of Shares by Holding or any similar arrangement which
would interfere with the sale of Holding's shares.

Other than as described above, Parent and Holding
have no plans or proposals which relate to or would
result in: (a) the acquisition by any person of addition-
al securities of the Issuer, or the disposition of secu-
rities of the Issuer; (b) an extraordinary corporate
transaction, such as a merger, reorganization or liquida-
tion, involving the Issuer or any of its subsidiaries;
(c) a sale or transfer of a material amount of assets of
the Issuer or any of its subsidiaries; (d) any change in
the present board of directors or management of the
Issuer, including any plans or proposals to change the
number or term of directors or to fill any existing
vacancies on the board; (e) any material change in the
present capitalization or dividend policy of the Issuer;
(f) any other material change in the Issuer's business or
corporate structure; (g) changes in the Issuer's charter,
bylaws or instruments corresponding thereto or any other
actions which may impede the acquisition of control of
the Issuer by any person; (h) a class of securities of
the Issuer to be delisted from a national securities
exchange or to cease to be authorized to be quoted in an
inter-dealer quotation system of a registered national
securities association; (i) a class of equity securities
of the Issuer becoming eligible for termination of regis-
tration pursuant to Section 12(g)(4) of the Securities
Exchange Act of 1934; or (j) any action similar to any of
those enumerated above.

Item 5. Interest in Securities of the Issuer

(a),(b) At the Closing, the Issuer delivered to
Holding the Shares. As a result, as of the date of this
Statement, Parent and Holding may be deemed to benefi-
cially own 1,277,778 shares of Common Stock for purposes
of Rule 13d-3 under the Securities and Exchange Act of
1934, as amended.

Except as described in paragraph (c) below, to the
best of Parent's and Holding's knowledge, none of the
directors or officers of Parent or Holding beneficially
owns any shares of Common Stock.

(c) The only transaction effected by Parent and
Holding with respect to the Common Stock is the consumma-
tion of the transactions contemplated by the Stock Pur-
chase Agreement and Stockholder's Agreement.

On February 22, 1995, Albert R. Schlesinger, Vice
President and Controller of Parent, purchased 750 shares
of Common Stock on the open market through a broker at a
price per share of $10.50.

To the best of Parent's and Holding's knowledge,
none of the directors or executive officers of Parent or
Holding have engaged in any other transactions with
respect to the Common Stock during the past 60 days.

(d) None.

(e) Not applicable.

Item 6. Contracts, Arrangements, Understandings or
Relationships With Respect to Securities of the
Issuer

Except as described in Items 3 and 4 above, there
are no contracts, arrangements, understandings or rela-
tionships (legal or otherwise) among the persons named in
Item 2 and between such persons and any person with
respect to any securities of the Issuer.

Item 7. Material to be Filed as Exhibits

1. Stock Purchase Agreement, dated as of October
20, 1994, by and among Ball Corporation,
Efratom Holding, Inc. and Datum Inc., as amend-
ed (conformed copy).

2. Stockholder's Agreement, dated as of March 17,
1995, by and between Efratom Holding, Inc. and
Datum Inc. (conformed copy).



SIGNATURE

After reasonable inquiry and to the best of its
knowledge and belief, the undersigned certifies that the
information set forth in this Statement is true, complete
and correct.

Dated: March 27, 1995

BALL CORPORATION

By: /s/ GEORGE A. SISSEL
George A. Sissel
Acting President and
Chief Executive Officer

EFRATOM HOLDING, INC.

By: /S/ DONOVAN B. HICKS
Donovan B. Hicks
President


APPENDIX A

The following tables set forth the name, residence
or business address and present principal occupation or
employment of each director and executive officer of Ball
Corporation and Efratom Holding, Inc. Each such person
is a citizen of the United States of America.

A. Directors and Executive Officers of Ball Corporation

Reporting Person Address Principal Occupation

DIRECTORS:

Delbert C. Staley 345 South High Street Chairman of the Board,
Muncie, Indiana 47305 Alcatel Network Systems,
Dallas, Texas

John F. Lehman 345 South High Street Chairman of the Board,
Muncie, Indiana 47305 Sperry Marine Inc., Char-
lottesville, Virginia;
Chairman, J.F. Lehman &
Company, New York, New
York

George A. Sissel 345 South High Street Acting President and Chief
Muncie, Indiana 47305 Executive Officer and Se-
nior Vice President, Cor-
porate Affairs; Corporate
Secretary and General
Counsel, Ball Corporation

Alvin Owsley 345 South High Street Chairman of the Board
Muncie, Indiana 47305

W. Thomas Stephens 345 South High Street Chairman, President and
Muncie, Indiana 47305 Chief Executive Officer,
Manville Corporation, Den-
ver, Colorado

William P. Stiritz 345 South High Street Chairman, President and
Muncie, Indiana 47305 Chief Executive Officer,
Ralston Purina Company,
St. Louis, Missouri

Howard M. Dean 345 South High Street Chairman of the Board and
Muncie, Indiana 47305 Chief Executive Officer,
Dean Foods Company, Frank-
lin Park, Illinois

John T. Hackett 345 South High Street Managing General Partner,
Muncie, Indiana 47305 CID Equity Partners, Indi-
anapolis, Indiana

Jan Nicholson 345 South High Street Managing Director of Capi-
Muncie, Indiana 47305 tal Markets Assurance Cor-
poration (CapMAC), New
York, New York
CORPORATE OFFICERS:

Richard E. Durbin 345 South High Street Vice President, Informa-
Muncie, Indiana 47305 tion Services

Duane E. Emerson 345 South High Street Senior Vice President,
Muncie, Indiana 47305 Administration

John A. Haas 345 South High Street Group Vice President
Muncie, Indiana 47305 (President and CEO, Ball
Glass Container Corpora-
tion)

Donovan B. Hicks 345 South High Street Group Vice President
Muncie, Indiana 47305 (President, Aerospace and
Communications Group)

R. David Hoover 345 South High Street Senior Vice President and
Muncie, Indiana 47305 Chief Financial Officer

Donald C. Lewis 345 South High Street Assistant Corporate Secre-
Muncie, Indiana 47305 tary and Associate General
Counsel
William A. Lincoln 345 South High Street Executive Vice President,
Muncie, Indiana 47305 Metal Container Operations

Elizabeth A. 345 South High Street Assistant Corporate Secre-
Overmyer Muncie, Indiana 47305 tary

Albert R. 345 South High Street Vice President and Con-
Schlesinger Muncie, Indiana 47305 troller

Raymond J. Seabrook 345 South High Street Vice President and Trea-
Muncie, Indiana 47305 surer

David B. Sheldon 345 South High Street Group Vice President
Muncie, Indiana 47305 (President, Metal Beverage
Container Group)

Harold L. Sohn 345 South High Street Vice President, Corporate
Muncie, Indiana 47305 Relations

David A. Westerlund 345 South High Street Vice President, Human Re-
Muncie, Indiana 47305 sources

B. Directors and Executive Officers of Efratom Holding, Inc.

Donovan B. Hicks 10 Longs Peak Drive President and
Broomfield, Colorado 80038 Director

Donald C. Lewis 10 Longs Peak Drive Vice President
Broomfield, Colorado 80038 and Assistant
Secretary and
Director

Hillary E. Johnson 10 Longs Peak Drive Secretary and
Broomfield, Colorado 80038 Director

J. Patrick 10 Longs Peak Drive Vice President
Dummigan Broomfield, Colorado 80038

Eugene P. Morgan 10 Longs Peak Drive Vice President
Broomfield, Colorado 80038 and Treasurer