Portfolio Update

BLACKROCK COMMODITIES INCOME INVESTMENT TRUST plc

All information is at 30 April 2012 and unaudited.

Performance at month end with net income reinvested

                        One    Three      Six      One    Three     Five
                      Month   Months   Months     Year     Years    Years
Net asset value       -3.0%    -7.6%    -4.0%   -17.1%     45.9%    25.4%
Share price           -4.1%    -6.7%     2.5%   -16.2%     43.6%    35.6%

Sources: Datastream, BlackRock

At month end
Net asset value - capital only:     121.85p
Net asset value - cum income**:     122.43p
Share price:                        124.63p
Premium to NAV (cum income):           1.8%
Net yield:                             4.6%
Gearing - cum income:                  0.0%
Total assets^^:                    £113.02m
Ordinary shares in issue:        92,308,000

On 16 April 2012, 250,000 shares were issued for proceeds of £309,534 following
which the issued share capital was increased to 92,308,000 ordinary shares. Since 
1 May 2012, a further 600,000 shares have been issued increasing the issued
share capital to 92,908,000.

**Includes net revenue of 0.58p.
^^includes current year revenue.

Sector                   % Total     Country                   % Total
Analysis              Cap Assets     Analysis               Cap Assets

Integrated Oil              30.2     Global                       27.8
Diversified                 20.6     USA                          21.4
Exploration & Production    11.9     Canada                       21.3
Copper                       5.7     Europe                        8.2
Oil Services                 5.0     Latin America                 7.9
Iron Ore                     4.6     Asia                          5.6
Oil Sands                    4.5     South Africa                  4.6
Gold                         3.6     Australia                     1.8
Coal                         3.3     China                         1.7
Fertilizer                   3.0     Africa                        0.7
Aluminium                    2.4     Current assets               (1.0)
Distribution                 2.2                                 -----
Tin                          1.5                                 100.0
Zinc                         0.9                                 =====
Platinum                     0.9
Nickel                       0.7
Current assets              (1.0)
                           -----
                           100.0
                           =====

Ten Largest Equity Investments (in alphabetical order)

Company                      Region of Risk

Anadarko Petroleum              USA
BHP Billiton                    Global
Chevron                         Global
ExxonMobil                      Global
Kumba Iron Ore                  South Africa
Occidental Petroleum            USA
Rio Tinto                       Global
Teck Resources                  Canada         
Total                           Global
Vale                            Latin America

Commenting on the markets, Richard Davis, representing the Investment Manager
noted:

Equity and commodity markets were weaker in April on the back of uncertainty
about the impending elections in France and Greece and mixed economic data out
of both the US and China.  In energy markets, Brent oil prices trended lower as
negotiations with Iran over their nuclear program progressed, thereby providing
some reassurance to markets around future oil supply.  A rise in year-on-year
OPEC production also removed some of the upward pressure on oil markets.  Brent
fell back to US$118.5/Bbl. Despite US natural gas prices falling to a 12 month
low in April, prices recovered slightly by the end of the month to finish at
US$2.1/MMBtu, a 5% month-on-month gain.

The threat of resource nationalism, a key risk across the natural resources
sector, re-emerged in April with the Argentinian government announcing its
intention to seize 51% of YPF, the Argentinian oil company, from parent company
Repsol.  Argentina has been an emerging source of supply as the country offers
exciting geological opportunities such as the Vaca Muerta, a large
unconventional resource in the Neuquén province which is expected to hold
recoverable reserves of 927 million barrels.  The expropriation of the company
by Argentina's government adds risk to the development of this resource.  The
shale industry in the country is still in its early stages and without the
expertise of international oil companies the project may face challenges and
delays, impacting future oil supply.

It has been over one year since the Fukushima nuclear disaster and Japan has
materially increased its imports, with oil demand in the country having risen
to its highest level in 3 years.  Japan currently has only one of the original
54 nuclear power stations still in operation, however this reactor is expected
to be switched off in early May.  This leaves Japan with a heavy reliance on
oil imports and a risk that in the event of a hot summer, they may not be able
to meet their energy requirements. 

In the metal markets, commodity demand fears have thus far looked to be
overstated, as steel production in China and other demand side indicators have
held comparatively firm.  Chinese steel production in March, for example, ran
at an annualised rate of 725 million tonnes, the second highest figure on
record and up 3.1% from February's figure (source: China's National Bureau of
Statistics).

The strength of Chinese steel activity has been reflected in the resilience of
the iron price. Spot prices in China have held firm above the US$140/tonne
level all year (source: CLSA).  Supply challenges have also played a crucial
role in keeping the dynamics underpinning prices constructive.  Iron ore
production growth faces significant challenges in our view, not least those
relating to infrastructure.  But, as in the early part of 2011, it has been
adverse weather conditions (cyclones in the Pilbara region of Western
Australia, for example) that have driven near term supply shortfalls in iron
ore.  Industry heavyweights Vale, BHP Billiton and Rio Tinto (who together
supply 64% of the world's seaborne iron ore market) reported a 12.4% decline in
their combined iron ore production for the first quarter this year versus the
final quarter of last year due to weather related obstacles.

Supply side challenges in the mining industry continue to be underestimated by
the market in our view. Industry participants are, unsurprisingly, more
cognisant and the message was highlighted at the CESCO copper conference hosted
in Chile in April at which predictions for another year of copper market
deficit were reinforced and the likelihood of continued mine disruptions
(whether linked to labour disputes, weather conditions or technical problems)
was a recurrent theme. 

BHP Billiton has invigorated an important debate about mining company strategy.
The mining giant has indicated that their capex plan is 'flexible'. The
messaging marks the first clear attempt by a major to address investor concerns
about capital allocation in the sector.  Capital discipline is likely to be key
to mining share performance as shareholders have made plain their desire for
higher pay-outs and prudent capital spending from mining companies.

21 May 2012

ENDS

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terminal).  Neither the contents of the Manager's website nor the contents of
any website accessible from hyperlinks on the Manager's website (or any other
website) is incorporated into, or forms part of, this announcement.