Exhibit 99.1
 TranS1 Inc. Reports Operating Results for the First Quarter of 2009
 Highlights:
 First quarter revenues increased 45% to $8.7 million
 889 TranS1 procedures performed globally in the quarter
 Gross margin was 82.2% for the quarter
 GAAP loss per share was $0.25 for the quarter
 Non-GAAP loss per share was $0.22 for the quarter




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Conference Call
  Non-GAAP Measures
  About TranS1 Inc.
 ®
 Forward-Looking Statements
  CONTACT:




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Three MonthsEnded March 31,2009
    
    
    2008Revenue
    
    $
    8,678
    
    
    $
    5,978Cost of revenue
    
    
    1,542
    
    
    
    1,038Gross profit
    
    
    7,136
    
    
    
    4,940Operating expenses:Research and development
    
    
    1,605
    
    
    
    1,215Sales and marketing
    
    
    9,150
    
    
    
    5,697General and administrative
    
    
    1,762
    
    
    
    1,407Total operating expenses
    
    
    12,517
    
    
    
    8,319Operating loss
    
    
    (5,381
    )
    
    
    (3,379
    )Interest income
    
    
    217
    
    
    
    940Net loss
    
    $
    (5,164
    )
    
    $
    (2,439
    )Net loss per common share  basic and diluted
    
    $
    (0.25
    )
    
    $
    (0.12
    )Weighted average common shares outstanding 
basic and diluted
    
    
    20,552
    
    
    
    19,930Stock-based compensation is included in
operating expenses in the
following categories:Cost of revenue
    
    $
    18
    
    
    $
    14Research and development
    
    
    44
    
    
    
    91Sales and marketing
    
    
    388
    
    
    
    275General and administrative
    
    
    193
    
    
    
    143$
    643
    
    
    $
    523




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2009
    
    
    2008GAAP net loss
    
    $
    (5,164
    )
    
    $
    (2,439
    )Stock based compensation
    
    
    643
    
    
    
    523Non-GAAP net loss
    
    $
    (4,521
    )
    
    $
    (1,916
    )Shares used in computing GAAP and
non-GAAP loss per share
    
    
    20,552
    
    
    
    19,930Non-GAAP loss per share
    
    $
    (0.22
    )
    
    $
    (0.10
    )




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March 31,
    
    
    Dec. 31,2009
    
    
    2008AssetsCurrent assets:Cash and cash equivalents
    
    $
    52,786
    
    
    $
    42,051Short-term investments
    
    
    19,269
    
    
    
    35,215Accounts receivable, net
    
    
    5,447
    
    
    
    4,812Inventory
    
    
    6,525
    
    
    
    6,369Prepaid expenses and other assets
    
    
    602
    
    
    
    632Total current assets
    
    
    84,629
    
    
    
    89,079Property and equipment, net
    
    
    1,460
    
    
    
    1,412Total assets
    
    $
    86,089
    
    
    $
    90,491Liabilities and Stockholders EquityCurrent liabilities:Accounts payable
    
    $
    2,944
    
    
    $
    2,896Accrued expenses
    
    
    2,059
    
    
    
    2,009Total current liabilities
    
    
    5,003
    
    
    
    4,905Stockholders equityCommon stock
    
    
    2
    
    
    
    2Additional paid-in capital
    
    
    134,171
    
    
    
    133,507Accumulated deficit
    
    $
    (53,087
    )
    
    $
    (47,923
    )Total stockholders equity
    
    
    81,086
    
    
    
    85,586Total liabilities and
stockholders equity
    
    $
    86,089
    
    
    $
    90,491




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##### 



Three MonthsEnded March 31,2009
    
    
    2008Cash flows from operating activities:Net loss
    
    $
    (5,164
    )
    
    $
    (2,439
    )Adjustments to reconcile net loss to
net cash used in operating activitiesDepreciation
    
    
    229
    
    
    
    170Stock-based compensation
    
    
    643
    
    
    
    523Allowance for excess and
obsolete inventory
    
    
    35
    
    
    
    (1
    )Provision for bad debts
    
    
    24
    
    
    
    18Changes in operating assets
and liabilities:(Increase) decrease in
accounts receivable
    
    
    (659
    )
    
    
    (317
    )(Increase) decrease in inventory
    
    
    (191
    )
    
    
    377(Increase) decrease in prepaid expenses
    
    
    30
    
    
    
    (31
    )Increase (decrease) in accounts payable
    
    
    48
    
    
    
    115Increase (decrease) in accrued expenses
    
    
    50
    
    
    
    (387
    )Net cash used in operating activities
    
    
    (4,955
    )
    
    
    (1,972
    )Cash flows from investing activities:Purchase of property and equipment
    
    
    (277
    )
    
    
    (420
    )Purchases of investments
    
    
    (2,973
    )
    
    
    (33,150
    )Sales and maturities of
short-term investments
    
    
    18,919
    
    
    
    9,825Net cash provided by (used in)
investing activities
    
    
    15,669
    
    
    
    (23,745
    )Cash flows from financing activities:Proceeds from issuance of common stock
    
    
    21
    
    
    
    44Net cash provided by (used in)
financing activities
    
    
    21
    
    
    
    44Net increase (decrease) in cash and
cash equivalents
    
    
    10,735
    
    
    
    (25,673
    )Cash and cash equivalents, beginning
of period
    
    
    42,051
    
    
    
    64,676Cash and cash equivalents, end of period
    
    $
    52,786
    
    
    $
    39,003